Isn't amazing the variety of responses to this question. Here a few of my favorities (keep in mind that we haven't eaten everywhere):

Resorts
Ohana's
Whispering Canyon Cafe
Boatwright's

Animal Knigdom
Flaming Tree BBQ

Magic Kingdom
Columbia Harbour House
Pecos Bill

DHS
50s Prime Time
Backlot Express

EPCOT
Le Cellier
Sunshine Seasons
Biergarten
Yakitori House
Yorkshire County Fish Shop

DTD
Wolfgang Puck Express
Raglan Road
Earl of Sandwich

Too many good choices...