i just got back from a disney world trip today and i've been there a few other times. is there anything specific you want to know?
here's a pretty good unofficial website. there's a lot of really good info there.
http://allears.net/index.htmla few things off the top of my head
*bring a few pairs of shoes because it rains quite often. i would suggest picking up some disposable panchos just in case.
*it's going to be hot and sticky. last week the heat index hit 115 after a rain and some triple digit heat.
*!!!fast passes are the key to not spending your entire vacation in lines!!! get them for what you want to ride as soon as they are available. you can cut 1.5 hour waits down to 10 minutes. certain rides like the new toy story 3d ride/game will be completely wiped out of fast passes FOR THE DAY within two hours of park opening. don't waste your fast passes on a non-major attraction. most rides that aren't huge attractions have waits of less than 30 minutes.
*eat or drink your way through the world section of epcot
*check out innoventions in epcot and the coca cola sponsored building (can't think of the name). cool something?...
*animal kingdom has stuff for everyone but there are less things to do. epcot has something for everyone, but adults will appreciate it more. hollywood studios has something for everyone, but definitely checkout the stunt show. show up 30 minutes before showtime. the magic kingdom is more suited for younger kids.
*plastic is accepted everywhere.
*a pleasant way to do the parks without beating yourself up is to spend the morning at a park, leave for lunch and a nap, and come back in the afternoon. if you're not pressed for time, there's not much of a reason to spend every minute at the parks.
*downtown disney is worth checking out. the boardwalk is not.