Were there 2 years ago with 5yo DS, and again this past summer for his 6th bday, and he LOVED sci-fi the best, it was the only one all the kids insisted on returning to. We also hit a bunch of the character buffets - CP, Tusker house character breakfast (best character interaction), Ohana breakfast (THIS ONE WAS AMAZING FOOD!!!), CRT (we booked this one for DD, but he liked this one quite well, surprisingly enough - got a little plastic sword at the door) and we did hoop de doo revue last year. I thought DS would be too young for it, and really booked it for my older kids, but all the kids loved it, actually all of us did - it was a good time, and the food was decent too.
For snacks, you can't beat the main street bakery, he loves their cinnamon rolls, and the giant ice cream cookies, and also the sleepy hollow ice cream floats, and the chocolate dipped micky ear rice krispie treats, well, that list could go on and on forever.......