I'm pretty sure there's packing lists all over this site! But I can't direct you to them exactly. I know Mary at
www.mousesavers.com has a packing list.
What I always take - and I've been a gazillion times! - is as little as possible! No one in my family likes to carry a back pack or a bunch of stuff so we don't worry about saving money on snacks and drinks by carrying our own. We take the basics into the park - A fanny pack with the following - tickets, our room key (which we charge everything to), a small amount of cash for the stuff you can't charge - usually no more then $50 and we rarely use it, ID and insurance cards, sunscreen, lip balm, bandaids, a few wet wipes, extra film and a little vial with Tylenol and my DH's medicines. We all wear visors or a hat and our camera bag has a loop for my DH to carry it on his belt.
I bring one nice outfit - by nice I mean "resort casual" for the one night we do something that requires something a little nicer - this year it will be Tchoup Chop. Other then that I only bring shorts and tops for clothes. I have a mini medicine kit for the room with more bandaids, some sort of blister prevention stuff (like those soft things Bandaid carries now for blisters) Alka Seltzer, antibiotic ointment, some sort of itch stuff and more pain killer type stuff.
Whatever toiletries you need at home you need on vacation and I always bring some sort of bubble bath or oil to pamper myself after a long day at the parks! I also like my own Bath & Body Works Body Wash and lotion so I bring that too!
Hope this helps! Make you out a list now and keep it handy to add to as you think of stuff.