I have many favorites, of course. How could I choose just one?
I love The Christmas Song (Chesnutts Roasting on an Open Fire) by Nat King Cole. This song is just awesome! I'll Be Home for Chritmas, I'm Dreaming of a White Christmas and Have Yourself a Merry Little Chritmas by Bing Crosby are also some more favorites!
Of non-traditional songs, I absolutely love George Strait's When it's Christmas Time in Texas. A Christmas song just for us Texans!

I also like All I Want for Chritmas is You by Mariah Carey.