A WDW stay without a visit (or two. OK last trip it was 3 because in staying at BWI we found you can order from the FF menu via room service) to FF is just not possible for us, LOL. We tend to eat at FF for Christmas Eve instead of the Day and have found the restaurant's food excellent in preparation, the service very professional yet personable and the decor conducive to the theme. One of the few Disney places where we
always order dessert as it's so worthy; extremely talented pastry chef.
I don't know whether Chefs de France offers a special menu for Christmas Day but keep in mind it has 2 different menus daily: a la carte and prix fixe.
Both solid choices and easy to get to via boat or walking. I'm sure there is a bus that takes you from the Boardwalk hotels to Epcot but never taken one since the other travel options were easy enough.
Have fun where you go. Your mouth is in for a treat
.