If a restaurant is not listed, then it served it's regular menu...Also - Note that Christmas day is the busiest day in the MK - Last year, the park closed to new visitors about 10:30 am (we were leaving the Poly by car around Noon, and there was a 2 hour back-up to get to the turn-around, because the park was full and they were not letting anyone park)--Although they do let guests into the park later in the day as some of the others leave - I believe that on-site guests have priority for that - and there is no guarantee that you would be let in......
Soooo - If you want to eat in the MK, I would plan on arriving early (first hour or 2 after opening at the latest) and staying all day...If you want to eat at a MK resort - then plan on taking Disney Transpo (bus) or giving yourself longer to get there and park (as there may be traffic)...Jill