Every toddler is so different. My DS's favorites were the flying dinosaurs and carpets (never got around to Dumbo), HM, Pirates, the Safari, Nemo ride. He LOVED the 3 Caballeros ride in Mexico and basically played peek-a-boo with all of the Donald Ducks. I thought he'd love Turtle Talk because he loves turtles, but he just couldn't sit still through it. He slept through FEA and fell asleep on iasw and the Carousel (while sitting on a horse with me next to him). He also loved the Lion King show. His favorite play area was definitely the light up carpets in the play area after the Figment ride.
We like ADRs because it's a way to escape the heat and we enjoy the character meals because we don't have to pay for him yet and then we don't have to wait in the meet and greet lines. DS seemed to really enjoy Garden Grill (amazing character interaction) and Crystal Palace (even though he had no prior exposure to Pooh and friends, he loved them). At SciFi, he wouldn't sit still in the booth. You can't put a highchair at the car booths, so something to consider there.