I'm a Scout leader, who has led hikes, and happy feet are my game.
1. Wear great-not good-but great tennis shoes. Make sure they are not heavy, because at the end of the day they will feel like they weigh 4 times more than in the morning.
2. Wear two pairs of socks that fit. Not too tight, and don't look like snow shoes. Pair 1 -closest to the feet- sock liners or thin cotton socks. Pair 2- closest to the shoe- thick socks made for walking/hiking. I love thorlos socks. You can get them made for any weather and the materials are wonderful. (God sent down Thorlos from heaven just like manna). Let me warn you- you will pay for Thorlos greatness.
3. Moleskin (Actual Moles were not harmed in process).

Buy it at Wal-Mart (comes in squares to cut to size). Great for hot spot. If blister forms, lance blister with needle, cover with gauze, moleskin on top.

Moleskin-not bandaids.
4. Scotchguard shoes against water.

Works for small splashes, not drenching. Since you will be WDW, and your feet will probably get denched, I suggest bringing extra footwear. Socks and shoes, and stowing it in a locker. Once the feet get wet, all the amazing magic in your shoes and socks goes into hibernation.
Now, I will get off my soapbox.
