Hi Keissa,
You'll definitely want to bring her to the Magic Kingdom, as this is the best park for toddlers. In particular, head to Fantasyland (located behind Cinderella Castle). She'll love The Many Adventures of Winnie the Pooh, the Carrousel, Dumbo, Peter Pan's Flight and It's a Small World. Be sure to pick up a Times Guide to see where and when she can meet her favorite characters.
The second park that I would bring her to, based on her age, is the Animal Kingdom. This is based on the fact that when my children were 2, the only attractions at Epcot that they truly enjoyed were The Seas with Nemo and Friends and Journey into Imagination. They were too small for the rest of them. Granted, we could have spent hours in the Seas looking at the fish (and we did). At Hollywood Studios, your little girl would enjoy
Disney Junior- Live on Stage. However, beyond that, when mine were toddlers, they didn't really enjoy Hollywood Studios because they didn't want to sit still for shows and they were too small for rides. Animal Kingdom has so many neat areas where you can view the animals and little ones always enjoy that. I recommend you bring her on the Kilimanjaro Safari. She'll also enjoy the
Maharajah Jungle Trek and the
Pangani Forest Exploration Trail where you can view many different birds and animals. She'll also enjoy taking the Wildlife Express Train to Rafiki's Planet Watch area where you can visit the Affection Section (petting zoo) and more.
Hope this helps and that your little girl has a magical first visit to Disney World,
Kaylene