Well, I checked the link for the 12 best songs and I haven't even heard of most of them! I thought their #2 song---John Lennon's 'Happy Christmas'---should have been #1.
My personal favorites (besides Happy Christmas):
Gabriel's Message (love the way Sting sings this)
I'll Be Home for Christmas
Have Yourself a Merry LIttle Christmas
O Holy Night
Snow ( by Loreena McKennitt; I love her music)
Rudolph the Red Nosed Reinideer (by Gene Autry, of course)