Well, if you're heading to WDW, I'd def. be at Epcot from Sept. 28th through Oct. 1st. Good ol' Jim has some nice surprises in store for you to celebrate the 25th. And it's also the opening of the Food and Wine festival, as well as the opening of the new Canada film.
Also, the National Treasures exhibit over at the American Adventure will open too, so please, get over there, take a look at it, and make some comments to Guest Relations on how good it looks. (if you like it of course) You have no idea how hard it was to get that exhibit approved. And positive comments would make some certain people in Epcot Management and some Imagineers very happy.