Hi Courtney!
Going from one Walt Disney World resort to another is probably the most difficult thing you will have to deal with during your magical vacation. Having your own car if you plan on going from one to another is the best option as there is no direct bus system.
Many of the resorts have special holiday decorations. The Yacht Club has their model train set up, the Beach Club has the chocolate carrousel, the Grand Floridian has their gingerbread house, and the Contemporary has their modern take of a gingerbread castle. The Wilderness Lodge has the most magnificent tree in the lobby and with the fireplace as a backdrop it is a most festive feeling. Not to be forgotten is the Fort Wilderness Resort where most of the RV campers will have their sites decorated with lights and blow-ups making it worth an evening drive around. Walt Disney World is full of
Holiday Traditions. You will certainly be able to park and visit resorts but that depends on parking availability. The Contemporary is often extremely difficult to enter unless you have a dining reservation so if you can it would be best to park at another monorail resort and take the monorail around. The Yacht and Beach Club resorts have construction happening right now making some of their parking lost. If there is any sort of convention or meeting going on their lots might be full as well.
It is certainly worth heading to the resorts and mid day is often best to see the decorations. Have your Magic Band with you so they can scan that at the guard stations and also have your drivers license if they ask to see that. They will then direct you to guest parking or valet parking which would be $25.
Enjoy the holiday magic. I am getting excited to see it all once again myself!