Hi, Sandra!
Welcome to the Disney Parks Moms Panel. I'm sure your little ones are very excited about visiting Walt Disney World! With a total of 4 and one-half days for your trip, your family will have enough time to experience all four Walt Disney World theme parks! I recommend visiting one park each day and returning to Magic Kingdom Park on the half day.
Since your daughter has special needs, I would suggest stopping at Guest Relations in the first theme park you visit to request a Guest Assistance Card (GAC). Based on the information you provide, the GAC will be coded to alert Cast Members at attractions and shows about any special accommodations your daughter may require. The GAC is not a "front-of-the-line" pass; however, it can be very beneficial to those guests needing alternate entrances or other types of accommodations, where available.
There are so many things to see and do at Walt Disney World for preschool-aged children! My space is limited here, but I can start by giving you my
top picks for preschoolers in Magic Kingdom Park (click on this link for more details on each attraction):
Enchanted Tales with Belle
Under the Sea - Journey of the Little Mermaid
The Many Adventures of Winnie the Pooh
Dumbo the Flying Elephant
Peter Pan's Flight
Mickey's PhilharMagic
Mad Tea Party
it's a small world
Jungle Cruise
Walt Disney's Enchanted Tiki Room
Swiss Family Treehouse
Prince Charming Regal Carrousel
Buzz Lightyear's Space Ranger Spin
If you'd like specific recommendations for meeting Disney characters, dining or resorts (or any other aspect of planning your trip), please write me back directly and I'll be happy to help you plan a more detailed itinerary. Be sure to include your vacation dates!