Wow that's a hard one..........
Buffet's - Chef Mickeys- I choose this as it is for everyone, the fab 5 are here, and the food is good, I have eaten both breakfast and dinner, and enjoyed them both. It's fun to wave your napkins around, and see the character, and the monorail going through CR, If you time it just right you could go out and watch the water parade, or ride the monorail down to the Poly and watch the fire works on the beach or head into MK very easy to get around.
Sit down without characters - It depends on where you will be park wise.
MK-LTT -
DHS - Brown Derby
AK - I would head over to AKL and have dinner at Boma, and go out and watch the animals, and check out this resort beautiful.
Epcot - Chef's, Tutto, Coral Reef -
DTD - I would do Rainforest or T-Rex or Planet Hollywood - When we go in a big group we order a appetizer's and share and make a meal off those and we have even shared a couple of desserts. I ran the cost and it was a lot less if we all order separate meals. When our DD's were around this age they love to eat like this, to this day when we go we have appetizer night,
Boardwalk - Flying fish hands down - very $$$$
Breakfast will be less expensive - But if you are only going to do 1 TS, I personal would do dinner.
Check out the menu's here and over on allears for selection and price.
Have a wonderful time.