We called really ahead of time for our Christmas Day and Christmas Eve meals. Whispering Canyon was really hard to get, but they have a special Christmas meal. (We ended up cancelling that one because we decided to do Christmas Eve at the studios so we could be at Osbourne Lights that day.. BTW we do not regret that since it was one of the most magical nights of our entire lives. People were hugging and dancing and telling each other Merry Christmas. We saw people crying and holding their families. It was amazing) We did 50's Primetime that day because it was the only ADR we could get at the Studios after having to change the WC one. For Christmas Day, we reserved LTT. LOVED the meal that day. Very Christmasy. MK was horrible, beyond horrible for crowds, so we ate a late lunch and watched the parade then went to DTD to watch Marley and Me. It was a great day. We were there from the 21 to the 2, so we were lucky enough to not have to fight the crowds on Christmas Day.
We have been that week the last 2 years, but we did not arrive at the parks until the 26 this year, but ADRs are still highly, highly recommended. On New Years Eve, people were having to sign up for 4 hour waits or just being turned away from every restaurant. Enjoy your trip!