There are times I realize I never married. When I read your post, I knew why. If I ended up with someone like your husband, I wouldn't be spending 1 - 2 weeks at Disney a year, I'd be looking at 10 - 20 at Sing-sing prison.
There are two problems I have with his attitude. First - and most important - how friggin' dare he to say you should lop off YOUR parents and cast them adrift because he doesn't want to have dinner with them? If it were his parents, would he say the same thing? That is beyond rude, and you MUST stand your ground and not let your parents be treated this way. Unless your parents want an early night, or volunteer to give you and hub a date night, the plans stand.
Second - after planning, deciding, booking, revising, finalizing...NOW he decides he wants input? Nope, sorry, thanks for playing. What you could do in the effort to compromise is ask your parents if they would take your son back to the hotel a few times - that gives you a chance and Prince Alarming to spend time with you. See how your son reacts - but make sure you get him plenty of rest. I have seen too many vacations tarnished because parents pushed the kids way past their limits and the results are kids out of sync and parents out of thier mind. A pool afternoon and a nap everyday would do wonders to help him along....and the pool time is a great time for the family to unwind and then go back to the parks when everyone feels they are at their best. If you feel your son can go further, try it, but be ready to bail when he hits that wall. Go with the flow and don't be disappointed if everything you planned doesn't work out.
Look at it this way, when you go down to Disney with your new husband in a few years, you will train this one better.