The best time to visit Disney World is during the fall/winter. Minus Halloween, Thanksgiving, and Christmas Disney World is not that crowded as other times of the year. Also, prices are significantly lower.
However, that means that you will be traveling during a time when the weather can vary. Living here, I can attest that one day it will be in the mid 70s and then the next it will be chilly and rainy in the 60s. So, you must come prepared if you are planning a fall/winter vacation to Disney World.
If you have never been to this theme park, most of it is outdoors. There is not a lot of shelter, except for the little stores throughout the parks. I remember it raining while there, and we had to stand in a small store for 30 minutes. Also, in the Animal Kingdom there is not a lot of shelter. Most of it is outdoors. So be aware of the weather if you are planning a day out there.
Like most people, people hop park to park or visit just one all day. It's essential that you have comfortable shoes or otherwise your feet will not be happy. I love my Sperry's and they are super comfortable. When walking around all day, all I think about is being comfortable. Think about cotton materials and stretchable pants or shorts. You don't want to feel restricted at all. Boyfriend jeans are the best during the fall because they provide just enough warmth but not overly too warm. And they are comfy!
Remember to take a sweater cardigan with you in the morning - as it is a little chilly (it can be in the low 50s in the morning sometimes). By the afternoon however, it's in the high 60s to low 70s. So make sure to wear a light t-shirt underneath.
The bag of this season is the backpack.You will love using it at Disney World. Your hands will be free, safe and secure while you go on the rides!
Have you been to Disney World/Land during the fall/winter? If so, what did you wear?