Figuring out your target travel days in advance is beneficial. You want to try to schedule the trip during an off-peak time period that is blessed with mild weather. This will help you in avoiding long lines for rides, events that are overcrowded, and heat stroke from walking around in 110 temperature highs. My trip took place over a week that began with Labor Day, which I discovered is one of the worst days to be there. It was so hot and there were tons of people there, finishing up their summer vacations and indulging in long weekends. However, from the day following, through to the end of my week, the crowd thinned out so much that there was hardly a wait for any rides or attractions, if any at all. There was still an overload of heat, but it became much more bearable. A positive thing is that all of the buildings are equipped with air conditioning, which we opted to wander in and out of when we began getting too hot. .
Travel to Walt Disney World (for those of us not fortunate enough to live in a comfortable driving distance) typically includes airfare, and a rental vehicle. The key to airfare and car rentals is booking early. The price for each usually rises as dates get closer, and availability is not as good. Sometimes if you're lucky, there will be a last minute price deal, but that means taking a risk of the airline or car rental place selling out on your travel days, or possibly having to pay a much higher price if there are no specials available, because it's last minute. That's your choice. Good luck!.
I highly recommend staying at a hotel on the Walt Disney World property. There are many advantages to this. The room rates can be as low as any typical hotel, or as high as a month's rent, depending on what you desire. The deciding factor here is how much time you plan on spending at your hotel. If you are planning on visiting as many as 6 parks, you will most likely not be spending much time in your room.