We've taken our toddlers to most of the places in Epcot. Coral Reef would be a great pic,
the moroccon restaurant has a belly dancer which my kids love
Normally I would say Italy but it might be closed when you are going
San Angel for reasons above- but if darkness is an issue you might want to avoid, at one point my son was terrified of dark places and this did NOT work
Garden Grill but I don't like the food- character interaction is terrific
Teppanyaki is great for hibachi to entertain
Rose and Crown is fast, on the water so they can watch the boats go back and forth
The only ones I might shy away from would be
Le Cellier- while good food, it is a longer meal and we had a mini meltdown there
France- both restaurants are great but geared more towards adults