White Christmas ties with Miracle on 34th Street (original not the 1990s remake) as my top Christmas movies. My mom always wanted to have Bing Crosby be her dad so we watched a lot of Bing when I was a kid.
Irving Berlin's "White Christmas" first shows up in Bing Crosby's previous movie Holiday Inn, then was spun into a movie of its own. Since then everyone seems to have taken their turn at "White Christmas".
Here is the original and an assortment of interesting covers:
CHRISTMAS SONGS OF THE DAY: