We have been singing this one in our family for generations.
http://www.youtube.com/watch?v=8baaH0UGiCo&feature=related
"Do You Know How Christmas Trees Are Grown"
LOL, that's funny.
Here is a link to some Christmas music; CLICK IMAGE
I actually like that song, it really is a beautiful little John Barry piece (despite all the mockings back on alt.fan.james-bond).
http://www.youtube.com/watch?v=Veju4PxhuGc
:p
People have probably already posted
Jingle Bell Rock
http://www.youtube.com/watch?v=n50r-EwCuLw
and
Feliz Navidad
http://www.youtube.com/watch?v=ihW56Xa3XGQ