Animal Kingdom:
Best - Flame Tree Barbecue
Worst - Chakrandi Chicken Shop
I loved the Flame Tree BBQ, though among the group it was evenly split. My only advice is to know there is a distinct difference between the BBQ sauces. Also, follow the trail to the dock with the many picnic tables and you'll share your meal with a water view, ducks, and the Expedition Everest construction. Finally, something about warm stir-fry in one of the busiest areas of the park, while watching people slosh away from Kali River Rapids just turned my stomach. Not only did I not like the food, but the scenery left more than a little to be desired, and the children playing shoeless in the fountains then going (again, shoeless) into the overcrowded bathrooms, just made me wish I had waited to eat elsewhere.
MGM:
No Best/Worst
To me nothing sticks out as great or terrible, though I have yet to try the ABC Commissary, which seems to be a favorite of many. I am a big fruit eater, so the Anaheim Produce Company is always an option, though the prices usually scare me. More than once we have recharged at the generic tasting Toy Story Pizza Planet, but each time we feel we should have just made reservations at 50's Primetime Cafe, Sci-Fi Drive-In Diner, or Mama Melrose's Restaurant Italiano.
Epcot:
Best - Lotus Blossom Cafe, Tangierine Cafe, Cantina de San Angel, Boulangerie Patisserie
Worst - Electric Umbrella, Liberty Inn
I go to Epcot with food constantly in the back of my mind. When I was younger it was my least favorite park, but now it rivals Magic Kingdom. The Lotus Blossom Cafe has extremely quick and cheap House Fried Rice, usually with little to no wait. The Tangierine Cafe has excellent wraps, and is a huge change of pace for your tastes, but I highly recommend you just go to eat dinner at Restaurant Marrakesh. Cantina de San Angel has alcohol, with decent mexican food and chairs on the water. Boulangerie Patisserie only gets mentioned because of the cheese and ham filled croissant and the breaded hotdog, and of course the dessert.
Liberty Inn and Electric Umbrella are just more burger stops. They are usually busy, and I find the theming too blah. The toppings bar always seems a little messy for my liking at the Electric Umbrella, and I can't really force myself to sit and eat a hamburger in America on my vacation, when I'm surrounded by so many other experiences.
Magic Kingdom:
Best - El Pirata Y el Perico, Pecos Bill Cafe
Worst - Pinocchio Village Haus, anything in Tomorrowland (haven't been to the new Tomorrowland Terrace Noodle Station)
Magic Kingdom doesn't really offer the best meals, but still we all enjoy the atmosphere of the Adventureland and Frontierland eateries. Pecos Bill is just your usual hamburger joint, but at least it isn't sandwiched inside Fantasyland like Pinocchio's. Personally, I really like El Pirata Y el Perico, though last time we visited it was closed. We all agree though that Tomorrowland's to be avoided when eating because it is too crowded. The theming is just non-existant, which sucks because you really need a great theme to stomach un-inspired food.
Aloha Isle's pineapple float, Casey's Corner's hotdog, and anything from the Main Street Bake Shop's arsenal however can get you to your hotel feeling satisfied for at least a little while.