We were on the dining plan, baby was still not ready for a regular high chair, and ate at the following (would go back to them all):
Whispering Canyon Cafe at Wilderness Lodge (late lunch) - was great as they had infant seats (slight recline, full plastic base) not just high chairs ... our server even brought an extra cloth napkin to line the infant seat with so it wasn't too cold on the baby's back. Definite family atmosphere here ... can be loud if you go at peak times.
Crystal Palace at MK (dinner) - loved it ... awesome buffet, baby totally LOVED the characters (Tigger, Pooh, Eeyore, Piglet) and again they had infant seats not just high chairs.
Ohanna (late dinner) ... liked the food, no infant seats (just high chairs). Played pass the baby ... but he was happy cuz he constantly got a new view.
SciFi Diner (late lunch) ... baby loved watching the movie clips, food was ok, was able to bring the stroller beside the "car".
Coral Reef (dinner) ... baby had fallen asleep in stroller so they let us wheel it right in beside our table. Awesome aquarium for the baby (and you) to look at while you dine.
Restaurant Marrakesh (dinner) ... nice comfy booth seating that the baby napped on while we ate. Not all seats are booths though.
Boma (dinner) ... nice comfy booth seating that the baby napped on while we ate. Again, not all seats are booths.
Hope this helps a bit.