Becklit, you had a few questions. I will deal with them in reverse order.
You mentioned (reluctantly) some past incidents when your husband lost his temper, and could these incidents have caused your son's problems?
Seriously - I doubt it. However, the tendency in your husband to have a short fuse COULD be interfering with your son's ability to control his own temper and to respond appropriately to his dad. We have a similar problem with difficult child 3 and husband, because in the past husband has tried to be the heavy authority figure and it has backfired, badly. NOw most of difficult child 3's oppositional behaviour is reserved for husband. If there is an unpleasant task to ask difficult child 3 to do, I now have to do it because for husband, difficult child 3 will almost automatically object. Instead, we try to reserve some positive fun stuff for husband & difficult child 3 to do together, to try to rebuild a good relationship.
However, this is after several years of using "Explosive Child" techniques (although we did see amazing improvement in difficult child 3's behaviour fairly quickly).
Your husband didn't cause these problems. There is something more that your difficult child 3 was probably born with, that requires a different approach to what people think of as the usual effective parenting methods.
And now your other question. Becklit, you asked, "s it okay to stick him in front of a game for my sanity?"
Yep.
That's my call, anyway. If your son finds that playing computer games helps him in any way, I would let him. However, it does need to be regulated, at least to a certain extent.
We live in a house full of computer games. We did try to strictly control it at first but trust me, difficult children will find legitimate ways in which to indulge their craving. I say LEGITIMATE ways, because they will swap games, borrow games, even do the same thing with game systems. They will go and play at friends' houses and get to play there. The more you try to restrict it, the more your game-obsessed child will resent restrictions which do not seem to be imposed as strictly on others.
So what do you do?
We re-thought the whole thing. Why were we so against computer games? After all, the kids are building a range of skills in fine motor coordination. With newer game systems like Wii, they're building gross motor as well. OK,the close screen stuff isn't good for eyes but it's not that bad, either, especially if you impose the same rest breaks that a responsible workplace imposes on its keyboard operators. Standard health rules and O H & S guidelines SHOULD be taught to ALL game-playing obsessed kids. If they learn them now, they will do well later, in the workplace.
However, kids do have other things they need to do in life. We need to manage self-care (washing, dressing, eating). We have chores and responsibilities. We have social interaction. Gaming shouldn't interfere with this.
After observing difficult child 1 (our first obsessed gamer) we could see tat for him, playing computer games actually helped in many ways. it also helped relax him. We did find though, that some games made him more tense and so we limited his play of such games. difficult child 3 was much worse with the games that unsettled him. We had to ban him from some games, based on how tense he would get when playing, and whether he had nightmares if he played them later in the evenings.
Home-schooling does increase the temptation to play computer games when the kid should be working. We even managed that one OK.
We put a number of things in place and looking back, I am pleased with what we did because by sheer fluke, we did things in harmony with "Explosive Child" methods.
Step 1 - respect the child, and the child's property. In many cases the computer game system, or at least the games, belong to the child. They may have been birthday or Christmas gifts, but you can't take them away without disrespecting the child. And remember - you, the parent, are teaching the child how to show respect. This means you show respect first and do not make your respect to them, to be conditional on their good behaviour. You need to find other ways to deal with misbehaviour. (I know this is controversial, but how often do we read on this site, of major tantrums surrounding a kid being banned from gaming for various periods of time, as punishment?)
Step 2 - still showing respect; involve the child in discussion and decisions surrounding game times. Chores need to be done, self-care needs to be taken care of. Gaming is permitted outside these parameters, but also to ensure balance and a good night's sleep, there needs to be some level of control (as I described) as well as a curfew for gaming. So, in discussion with the child, ask THEM to help set the boundaries. Don't be afraid - this can play into your hands remarkably well.
Example: difficult child 1 was gaming almost constantly. They were games he'd bought himself with his own money, so I couldn't confiscate them. Of course, I could always shut off the household electricity because I paid THOSE bills. So he knew I had him. But he was old enough for common sense, too. He was home-schooling at the time and would often retreat into gaming to ease his stress. But schooling added to his stress and I wasn't happy about this used as an escape. he had to learn to face it.
So I said to him, "YOU define how many hours a day you can play computer games."
He sensed an opportunity ripe for exploitation. "Six hours a day!" he announced triumphantly, thinking he had just conned me, big-time.
"Done!" I said. "But you must spend equal time on schoolwork!"
We set up a log book. He had to note the time and sign in when he played computer games, signing off and logging off when he stopped. Similarly, we had a log for schoolwork. He thought this was marvellous, because it seemed to him that he spent ALL his time on schoolwork and not enough on games, when to me it seemed the other way around.
It took about three days of this, before he cried, "Uncle!"
It was a shock to him to realise just how much gaming he had been doing. He was clocking up his six hours a day incredibly fast. From that point, we were able to compromise. When it was NOT game time, difficult child 1 voluntarily gave me a vital component of his game system, which I kept in my pocket. Also at other times when he had an exam to study for, for example, difficult child 1 would announce, "No gaming for four days, until after my exam."
I would hold the component (or leads, or power supply) until the time was up.
Step 3 - assess the games. Sit and watch the kid play. Ideally, games should be assessed before they come into the home but you might start doing this but it can quickly get away from you. Plus, kids swap. What you need to do - work out your own rating, based on your own understanding of your child. For example, difficult child 1 is ten years older than difficult child 3. The older one could handle some quite 'heavy' games, but I banned them from being played in difficult child 3's presence. The decree - no maiming, no blood. Preferably no criminal activity being encouraged. So difficult child 1 found some games where bloodshed was an option that could be turned off. Instead of lying in a bloodied heap, the corpse would be unmarked and would gradually fade. Hmm... not sure if I was happy, but I let it pass.
The Star Wars Lego version - the kids love it. The humour in it is great, very subtle sometimes. If you know the movies, you will REALLY enjoy the satire. So both boys enjoy the game, on multiple levels.
Some games caused problems for difficult child 3 for reasons we just couldn't understand. These games were therefore banned after dinnertime. We found by trial and error what time he had to stop playing these games in order to have an uninterrupted night.
Step 4 - find "good" games. That is "good" from a parental point of view. There are some really great computer games which are more like puzzles, quiet brain-teasers. A lot of educational games are little more than study and revision with computer graphics. We had more categories, games which are permitted during school hours. Other categories again - games permitted for quiet wind-down times. And more - games for family together play-time. We even brought in gaming together as personal reward for difficult child 3's good behaviour - a meltdown-free day earned him 15 minutes' gaming with me as play partner. This was wonderful in helping him adjust to avoiding meltdowns.
On the news today has been research announcement that if we keep exercising our brain and challenging ourselves with new tasks, we can stave off brain aging. More games are being brought out which make use of this.
So maybe our kids have been right all along?
Our current rules - difficult child 3 may play games before school. When he attended mainstream, gaming was only permitted before school, once he was completely ready to leave. After school - this was negotiable, but we tried to get homework done first, then gaming. But that's because of the need to get homework done while there's a trace of medications on board. Now, there is no homework. difficult child 3 goes straight to his games when school finishes. However, he has been staying with schoolwork longer in order to complete a task. HIS choice; a very mature one.
Games must stop at any time, to do chores. We do allow a reasonable amount of time to get the game to a "pause" point, or somewhere that it can be saved. We do not summarily switch games off, no matter how tempting it may be. Mind you, I have threatened to shut off the house power supply...
At night, gaming must stop half an hour before "lights out". We have been able to lift the restriction on types of games played, once difficult child 3 showed he could handle it.
There have been benefits to allowing our kids to play computer games as much as they do.
First - the boys are very much in demand in the neighbourhood, as both a repository of games and also a fount of wisdom (and cheat sheets). Do not be alarmed by cheat sheets - they are a logical way of dealing with frustration and have been made available in most cases by the manufacturers.
Second - our boys are not only skilled at how to play these games, but they have transferred these skills to the hardware surrounding games as well as computers in general. difficult child 3 is now studying software technology as a school subject, and acing it. He is already fairly sure tat he wants to work with computers as a career path.
With both boys - knowing that we will not be unreasonable about gaming, actually helps them to relax about it themselves. They have that sense of security. As a result, they are less inclined to sneak game time when they should be doing other things. We allow a bit of flexibility, so they won't be fussing over a game not quite finished, and that way we get more productivity out of them when we need to.
A lot of people are still very critical of how much we let our kids play various game systems. mother in law comments that whenever we go shopping, difficult child 3's Nintendo DS (hand-held) seems almost surgically attached to him. husband's friends at the train track (where he often takes difficult child 3) have also expressed concern and have been finding tasks for difficult child 3 to do, to get him away from his gaming. difficult child 3 will happily do these tasks but will instantly pick up his DS at the first opportunity. It's his choice.
But because he has choice, he now does other things. He watches movies. He visits friends. He does read books.
This works for us. And our boys are doing very well, better than expected for both of them.
Marg
Use a firm tone and send him to his room. He is overwhelmed and angry and does not know how to deal with-what's going on in his head. It will also keep him away from the other kids. (I hope he's good about going to his room.) 
