In a word: They suck!
I'm not a big fan of Christmas songs at all. They do my nut in. I can't Paul McCartney going "Simply havin' a wonderful Christmas time" over and over again. Also I hate that song that just goes "Ding a ling a ling la ling" over and over again!!
Having said that there is perhaps one that I actually like which is Run Run Rudolph by Chuck Berry I think.