Crappy background music, bad lyrics, doesn't seem to fit right. Same as any other type of song.
There are a few that I like, though in some cases it's specific versions of the song, but not necessarily others.
Have Yourself A Merry Little Christmas. This version:
I just think that these lyrics make more sense to me than "hang a shining star upon the highest bough".
I Want to Come Home for Christmas, Marvin Gaye
The Christmas Waltz, Karen Carpenter, Grown Up Christmas List, Amy Grant version, Please Come Home for Christmas The Eagles, Baby It's Cold Outside Dean Martin, Zat You Santa Claus Louis Armstrong, We Should Be Together For Christmas Tamara Tunie version. A few others.