There are some very classic Christmas music out there. I'm a fan of music, so that makes me an expert on good Christmas music. Here's a list of my favorites, these are the songs that I actually wouldn't mind listening to year round.
5. I Saw Three Ships - Sting
Don't remember the first time I heard this song, but I do know it was on a cassette. I really dug the tune, and Sting plays it at a very nice cadence.
4. O Come, O Come, Emmanuel - Punch Brothers
I dig a great folk Christmas song. This one is one of the best. Punch Brothers is probably one of the most talented ensemble of folk musicians. They do this song a great justice, with spectacular fiddle play.
3. God Rest Ye Merry Gentlemen / We Three Kings - Barenaked Ladies (feat. Sarah McLachlan)
God Rest Ye Merry Gentlemen is probably my favorite classic Christmas song. I loved the way the music goes from a bit punchy in the verses, then the smooth 'Star of wonder/Star of night'. This version in particular puts Barenaked Ladies very unique style on the song, and McLachlan's overtones balance very nicely.
2. A Christmas Song - Dave Matthews and Tim Reynolds
One of my all time favorite musicians and a very well written and played song. Slowly played with a full sound although only with two guitars and a Dave's vocals.
1. Christmas / Sarajevo (Carol of the Bells) - Trans Siberian Orchestra
Carol of the Bells is a great song in and of itself, but TSO does something with this song and elevates it even higher. I love this song so much, in college I actually arranged a 3 part guitar version of the Carol that merged into God Rest Ye Merry Gentlemen. Wanted to perform it with a couple guys, but could never get together long enough to hash it out.