My boys (6 & 10) liked T-Rex, but I found it rather loud. Still, its worth going to once. Rain Forest is also good.
Others have made some great suggestions, so I'll just add a few of the other places my kids like.
They like any place where there is something moving (typical boys) - The Garden Grill with the rotating booths and ability to see part of the land ride. The little CS place near IASW where they can watch the boats being loaded. San Angel Inn restaurant where they can watch the riders. Cosmic Rays where they can watch Sony Eclipse.