If you are staying at a Disney Resort, you do not have to worry about park hopping--you're admitted even after "capacity" is reached.
Liberty Tree Tavern at MK and 50s Prime Time Cafe both serve very traditional home cooked Christmas at your Grandma's meals, and are themed wonderfully.
Ohana at the Polynesian is also an unbelievably good, filling meal. And the majority of World Showcase restaurants have very high marks from patrons, so it may be fun to try new things.
We leave for Disney the day after Christmas. And we are looking for a good place for New Years Eve dinner in Epcot--maybe Les Chefs de France b/c I speak french, we always wanted to try, and we want to celebrate new years at a "country" that celebrates their real new years during our dinner time hours....did that make sense?? haha