First off, I would like to thank the Windsor Family (all eight of you!) for the questions about your upcoming trip. I am not the answering service you may think I am, but I am willing to help out where I can. In that vein, I will answer the common theme you all seem to have: You have no idea what to wear. [This will also satisfy you lurkers who are also hitting my blog via Google.] Think of the following as some suggestions.
Comfortable Shoes. This is the Number One Most Important Thing. You will be walking 5-10 miles each day, depending on how enthusiastic you are. Leave all the stylish stuff at home and think of survival. Wear socks.
Loose, light-colored clothes. Shorts are a good idea.
Hat. I prefer a baseball cap, but you can wear anything. The idea is to keep the sun off of your head and face.
Sunscreen. No one wears the solid zinc sulfate stuff other than babies inside their diapers. It does you no good to get burned soon after arrival.
Sunglasses. Mandatory because you will be going in and out of the sun regularly. This will make things easier on your eyes.
Ladies, if you are easily chilled, consider a light windbreaker also. Put it on before you enter the venues that have their industrial air conditioning cranked down to 60F. I have seen dozens of lightly clad ladies shivering with crossed arms in such conditions.
For summer travel, consider bringing ponchos. Florida gets lots of showers (besides the hurricanes) that last 15-30 minutes. A poncho is light, compact and easily donned. Of course you can buy the Disney versions with Mickey on the back for $8 each when you are here in the rain.
Also, seriously consider a backpack. It makes it easy to carry supplies, such as a lunch/snack, and water. An insulated 2-liter jug packed with ice water will save you from standing in lines to buy over-priced drinks. Water is still free at Disney, although you can buy the expensive bottled stuff too.
Remember: Everything is cheaper off Disney property.