Hi Lisa! You definitely will want Santa to find you on Christmas and Disney will agree with you. We have spent a few holidays at one of the resorts and also enjoy having a small tree in our room to make it more festive.
Packages can be sent to your resort in advance. Be sure and put the name that is on the reservation and also your check-in date on the address. You can find the
Resort Address on the main site page. Be sure not to send anything too far in advance as things can tend to be put aside especially during busy times. Try to gauge it to arrive just 3-4 days ahead of your desired time.
Some resorts will charge for packages to be received. Please review this
Mail Service page. Most of the resorts who have convention services will be the ones who charge but you can also call the Art of Animation ahead of time to check their policies.
Another quick thought for you to ponder. When we traveled at this time of year to Disney it was impossible for us to consider bringing all of the kid's gifts. Shipping to and from was going to be expensive. I chose to take pictures of many of their gifts and then wrapped the picture in an envelope so they had things to open on Christmas morning. They were excited about the toys that awaited them the minute they got home and we didn't have to worry about getting everything there in one piece. Of course we had a couple of toys but basically they never had that much time to play since our days were in the parks enjoying the attractions.