My kids (10,8) love Margaritaville. It is a fun place to eat and there are people on stilts walking around making balloon hats for the kids. My DS loves NBA City. It's all basketball and if your boys like basketball, they will love it. The kids menu there is fun too. It has a design your own jersey, match the team names with the city, and other b-ball related activities. If you are into Nascar, there is a Nascar cafe in Citywalk also.
At IOA, we like to eat at Mythos. The food is out of this world. If you are looking for something besides the normal hamburger fare, try Mythos. It's fine dining in a theme park atmosphere. Sounds weird doesn't it, but just go...it's great! The kids like to eat there because it's like you are in a cave. We also enjoyed the Enchanted Oak. We have only eaten in US once and that was at the International Food and Film Festival. Whatever you do, don't go there.