Silver Bells, closely followed by I Heard The Bells On Christmas Day, Rocking Around The Christmas Tree and Blue Christmas. Honorable mentions to Christmas In Jail and the classic Christmas With The Devil by Spinal Tap!
I agree with Blue Christmas. Brings back memories of being away from family on Christmases past.
"and the classic Christmas With The Devil by Spinal Tap!"
There's a very fine line between stupid and clever, and that song straddles it with ease.
I also like that bizarre "carol" sung by a little boy that starts with "There's something stuck up in the chimney, and I don't know what it is...". Cruel but hilarious, just like Christmas in the RATL04 household!