We've had Whispering Canyon for lunch (as an AP holder I get a discount at lunch, not dinner). The atmosphere was great, DS loved the lincoln logs and kept wanting to go back to play after we were seated. At 9 years old (when we went this past Dec) he felt that he was too big for the stick pony races but I made him do them anyway and I think he liked it ok - probably would have been better if he had a friend with him or he was younger. We did not experience any of the antics that you hear about, but I've also heard they are cutting back on those. The food was delicious and the server was nice and laid back. We enjoyed exploring Wilderness Lodge and after lunch we rented a Searacer then played tether ball on the beach. It was a great way to spend an afternoon. I would recommend it if you are staying at Wilderness Lodge or if you have some time on your hands.
Crystal Palace we had for breakfast when ds was 8. We loved the characters. The food was good, but we aren't big breakfast eaters. Usually granola, fruit, or yogurt. We were with friends so ds did enjoy the hip hip hooray parade. We would like to try Crystal Palace again for lunch or dinner.
Chef Mickey's for dinner is fun. We think the food is very good for a buffet. Minnie is a big flirt with the men and boys. All the characters are great fun, especially Goofy. DS likes the spinning napkin ruckus! It is a great way to see characters without standing in line.
Also, we loved Ohanas Best Friends Breakfast with Lilo and Stitch (at the Poly). Even though we don't usually eat a hearty breakfast, we did enjoy the atmosphere, the view, and the characters. Stitch is ds's favorite character. The juice is awesome and they offer fruit. We did it in 07 but when we visited the end of 08, we did not do it. DS said he really missed it and asked if we could make it our one character breakfast from now on.
Also, we absolutely love Coral Reef for the atmosphere. The steak is good if you don't like seafood.
Also, T-Rex at Downtown Disney had just opened when we were there in December. It is not on the dining plan. They do offer a discount for AP holders. The food was great, the staff was great and ds built a dinosaur in the Build-A-Dino workshop.
I know you did not ask about cs but I have to say that Pizzafari in AK has spaghetti and meatballs on the kids menu and they are awesome! Other than the food courts this is the only cs kid's spaghetti that I know of. Now that ds (at 10) is a Disney "adult" we are trying to figure out how to get that in an adult size! You may want to check it out for your little guys.