We just got back, our daughter is barely 2.5 and we went on nearly everything at MK except the rollercoasters (although she went on Barnstormers and loved it!)and Stitches Great Escape(no loss there-lol). She loved Buzz Lightyear, Peter Pan, the Carrousel, Mickey's PhilharMagic, Magic Carpets, Dumbo, etc. (we were there nearly one full day plus for the
MNSSHP, otherwise we wouldn't have made it on all the rides)
As far as Epcot, she didn't do too much there. Unfortunantly Living Seas was closed. She did the IMagination ride, the Spaceship Earth, and walked around the lands (she did the little boat ride in Mexico, where we ate). She was a sport though. It was geared more for my son's ages (7.5, 6.5) A hint though, there's a fun little play area in the waiting area for Mission Space, I was hanging out in the gift shop and decided to go back there, and was glad I did.
MGM -she loved Playhouse Disney show, Little Mermaid, Muppet show. We only spent half a day there, but she probably would have like Beauty and the Beast and Fantasmic.
Animal Kingdom-she did the safari, the small ride in Dino Land, (she slept through Bugs Life, which I'm glad because even my boys were a little scared), she mostly liked the animals. Most of the rides were geared for older kids. We didn't get to see the shows(Lion King and Pocohantas), although I'm sure she would have liked those.
Hope that helps. I was glad she was able to enjoy so much, I was worried she'd get bored.
Jeni