Unquestionably, Vince Guaraldi's "My Little Drum" (off the Charlie Brown Xmas album). His riff on Little Drummer Boy, not quite the same. It's light, airy, filled with joy and mood. The instrumental fills are beautiful. Almost brings tears to my eyes when I hear it.
Almost any jazzy rendition of A Christmas Song works for me as well..good female vocal, instrumental, whatever.
Another one, could not find a legal recording of it to post, is Larry Carlton's version of My Favorite Things (yeah, Sound Of Music, but on his Christmas At My House album. spectacular, particularly if you like jazz guitar.