Have you checked out the virtual scrapbook at the top of this forum? Here's the link:
http://www.disboards.com/showthread.php?t=957926
There are lots of great pages there to give you ideas.
As for supplies, I think the basics are:
-a paper trimmer for cutting your photos and paper
-good scissors
-adhesive...there are lots of choices out there. I like Zig glue pens and the ATG 714 tape gun
-colored cardstock in whatever size you want to scrap (I like 12 x 12)
-archival quality pens for journaling
To me, that's the basic list. Then there are SO many other things you can use....punches, eyelets, die cut systems, glitter, stickers.....the list is endless. I started scrapping in January 2007 with one package of colored cardstock, one package of patterned paper, some stickers, and photo mounting squares, and that's it. I still do relatively simple pages, but I use the Cricut diecut machine for my letters and some of my embellishments.
I don't think that Disney World has a particularly great assortment of scrapping stuff. I used very little of what I bought there last year and my trip album is more than 50 pages. I would suggest concentrating on great photos and mementos to bring back with you more than the supplies that they sell.