I was at WDW last April with my DS14, DS11, and his 12-yr-old friend. Disney Quest is great, Blizzard Beach is great, but any resort pool is good too. Test Track and Mission Space and Soarin at Epcot; at MK, Space Mountain, Splash Mountain, and Big Thunder Mountain Railroad; at MGM, it's Rock'n'Roller Coaster and Tower of Terror; Animal Kingdom, the Safari, Kali River Rapids, Dinosaur, and Everest.
Of course, there are lots of other good ones too, but those are the must-do's for my guys.