In MK, Pecos Bill's has a great toppings bar. I especially enjoy dunking my french friens in the cheese sauce. Columbia Harbor House has a great tuna salad sandwich, and my kids love the fried fish and chicken strips here. If you're not looking for a whole meal, the Main Street Bakery has some great snacks. (We love grabbing cinnamon rolls and fruit salad from here for breakfast!)
AK has the best cs. Everything at Tusker House is excellent. My kids love the rotisserie chicken, and I love both the grilled chicken salad and the wrap w/ corn chowder. At Flame Tree, we've only ever had the pulled pork sandwich and the fresh fruit salad (love that pineapple!!). Both were great! During our October trip, the kids really wanted pizza from Pizzafari. We didn't expect much from this, but the pizza was really quite good. (Sorry, the breadsticks were NOT!)
At Epcot, I've enjoyed both the roast beef and the smoked turkey sandwiches lately. Usually, we eat TS here; so I can't really comment on the other CS restaurants. Dh and older ds did enjoy a dinner in the Land Pavillion during our May trip.
MGM....We've had so many bad meals here over the years that we haven't even had a snack here in ages and ages. It seems as if the reviews are getting better. Perhaps we'll be daring during our upcoming December trip and try a CS meal here.