So tough to decide, as they do change from time to time. Our most recent visits, these have been favorites:
Boathouse: great lunch or dinner menu, such a variety of options, great service
La Hacienda: love the guac here and the shrimp tacos...and the margarita flight to go with them; it's a somewhat inexpensive option and easy to do a walk-up usually
Wine Bar George: not a big variety of food here, but flaming cheese is the winner...can you go wrong with cheese?
Sebastians: We've only visited once, so not a lot of data but I did enjoy the rice and some of the meats...the chicken is kinda blah. The dessert is awesome too...for being a non-chocolate dessert.
Runner-Ups:
Story Book Dining: Wow how I love this place, but it's so much food and we just end up leaving sooo full. I wish we could split meals here.
Spice Road Table: We have only tried this once, but really enjoyed our experience here and would love to go back
These are all lunch or dinner options. Steakhouse 71 or GF Cafe would be our breakfast go to places, but S71 can be hit or miss on our favorite there -- the bacon cheddar grits. DH loves the steak and eggs at GF Cafe.
Honestly we visit Manginos at Shades of Green quite a lot because they have great food at reasonable prices and we don't need a reservation, but that's not a TRUE Disney restaurant and many people can't visit there.