My two are the same age although my oldest is a girl. We had our first trip at the beginning of the month and I also asked this question and got some good replies!
IMO, as you have boys, you HAVE to do Buzz Lightyear! There's also Big Thunder Mountain (big favourite with my 6 year old), Peter Pan, Pinocchio, Autopia, Space Tours, Dumbo, Parachutes. They also liked the stunt show in the Studios.
Suzie.