As intrinsically linked as nutmeg and eggnog, both of these Irving Berlin musicals boast Bing Crosby warbling "White Christmas"-and the holiday simply isn't Christmas without at least one viewing of Ba-Ba Bing crooning to Marjorie Reynolds/ Rosemary Clooney, right? Your basic boy meets/loses/wins girl story is the guts of both songfests with Fred Astaire/Danny Kaye providing the dance expertise and comic relief. You may know the songs and dialogue by heart but it never gets old.