On Chris Isaak's recent Christmas album (which I quite enjoy) he wrote "Brightest Star," the first overtly Christian Christmas song that I can recall being written by a mainstream rock artist in... well, maybe ever.
My wife and I have a Christmas music collection that is waaaay too large to be healthy, so I mostly listen to my own custom mixes, but for complete albums, my perennial faves include Leon Redbone's Christmas Island, Squirrel Nut Zippers' Christmas Caravan, Maddy Prior's A Tapestry of Carols, The Carol Album by Andrew Parrott and the Taverner Consort, and of course A Charlie Brown Christmas.
And, c'mon guys-- am I REALLY the only one that's enjoying Bob Dylan's Christmas in the Heart?