Thanks for your replies, and it really helps just to get clarity on things I already know but have trouble with. SWOT, I thought about your advice and I've always admired the way you can cut to the chase in a straightforward manner. I had been mulling over what do I say, how do I set boundaries, etc., and I just decided to think of the main things and go from there, not try to sugarcoat anything. So today I told him that he really needs to get serious about getting a job, that it's a critical thing. He said that, after the way his dad talked to him the other night, he's super motivated to get a job and move out. So maybe the fight wasn't such a bad thing?
I also told him I'm not buying him any more fast food, that he can eat whatever's on hand in the house or I would even give him money to buy real food that he likes at the grocery store. I said I'm not going to live with people walking on eggshells around him and that he needs to be more civil with everyone. And I told him that his constant criticism (ie. "there's only garbage for food in this house") needs to stop. He said OK to all this, but of course it remains to be seen if he'll try to comply. I didn't set out any real deadlines or consequences, so I feel like the talk might have been too open-ended, but I just feel like I'll start with these ideas and revisit them when needed.
I don't cook him special meals, but I do let him and his wife eat with us if we're actually sitting down to eat and I let them have run of the leftovers. They've actually bought some groceries with wife's paycheck today, so I'm not that concerned about the food except that it irks me to have him begging for takeout or fast food when he's just too lazy to make anything at home.
Scent of Cedar, he has been applying for jobs but mainly online, with no responses so far. He has spent the last few weeks working for free with his wife's father to get his community service hours he needs for court. I was glad to see that he did that, at least. He usually does well on the job, but it's the applying and getting the job that he avoids.
In a daze, thanks for asking about my other son. He was doing well for a time with his new job, and his boss was going to pay for training so he could be promoted, etc. But then he quit (suspect he was fired for too many "sick" days) and he and the family have now moved to a small town to live with his wife's family. He's unemployed and taking care of the kids while his wife works. Unfortunately, he's still addicted to heroin, so I don't know what will happen with him long term. I see them infrequently now, maybe once every month or so.