Northern Exposure: The episode called Seoul Mates. It’s the one where Holling sings Ave Maria to Shelley.
West Wing: Noel. This is the best of them all, my personal favorite, it’s the one where Leo tells the story to Josh that begins, “A man falls into a hole …”
West Wing: In Excelsis Deo, the one where Toby arranges for the burial of a homeless vet. (Aaron Sorkin can really do Christmas, apparently.)
Bones: The Man in the Fallout Shelter, this is the one where they are all quarantined in the lab over Christmas.
Buffy the Vampire Slayer: Amends. The one where it snows at the end.
Roswell: A Roswell Christmas Carol. This is the one where Max heals all the children at the hospital.
I didn’t get to the Christmas episodes of the X Files. I also loved the two Newsradio Christmas episodes that I watched, but really, they were barely Christmas-y, and were great because this show was always great.