We always watch a movie on Christmas Eve and I tend to get a dvd in rather than relying on the chance of something suitable being on.
It gets harder as they get older to find something we'd enjoy. We did Die Hard last year and Planes Trains and Automobiles (i know it's technically Thanksgiving, but it's lose enough :o ) the year before.
They are 15 and a half and 14 and a half, so realistically anything up to a 15 is fine.