The Grand Floridian is THE best of the decorations, and has so much more to offer than at the other resorts. They have the lifesized Gingerbread house, a model train around a miniature Christmas village, and of course the huge Victorian Christmas tree. Everywhere you turn, there is something Christmas-y!
The Wilderness Lodge also lends itself to the Christmas season. It is very rustic, and cozy, with the log interior, large Christmas tree and the rockers by the fireplace. Unfortunately, you can't see the fire, like you used to!
The Beach Club has much better decorations than the Yacht Club. The Yacht Club really had nothing special, just a tree. The Beach Club also had the miniature carousel as well as the tree.
As for the Animal Kingdom Lodge, haven't seen any pictures, or been there for Christmas... it wasn't finished when we were there in Dec of 2000, and we didn't get over there in January this year. I can imagine it could be similar to WL, as the archetecture is much the same, only it would be themed to African, instead of the American Northwest.