Oh - a couple more hints. You did NOT say if you are staying "on the property" (aka at a Disney Hotel). If you are, you will find that the Monorail/buses tend to make a car useless - they just work. At that point, hire a car service from the airport to your resort. Most (all?) will stop at the local supermarket, and you can pick up a bunch of stuff, and save more $$ (Hint - your wallet is the biggest thing at risk at the resort)

The hotels are more than glad to accept packages for you, and ship stuff home - you can ship a lot of your stuff down ahead of time

The stores in the parks will all ship to your hotel for pickup (makes it easier to seperate you from your $$)

Another hint - stick your wallet and CELL PHONE in ziplock bags. I went to soak my feet in the hot tube - I fell in - 1 soggy wallet, and ruined cell phone later, I learned that lesson