Though not traditional, I find the jazz interpretations a nice break from the classical oriented. Jim mentioned listening to the Kenny G christmas album (in another thread) and noted this IS some pretty music, and I concur.
My favorite would be "Peter White - Songs Of The Season" another "pretty music" and immensly enjoyable holiday album. Very well recorded and of course Peter's rich full bodied acoustic guitar. Some samples can be heard here.
What's your favorite in this genre?