The Muppets Xmas Carol rules. I also love Mickey's Xmas Carol, w/ a pre-Duck Tales Uncle Scrooge. I also j'adore A Charlie Brown Xmas (which, btw, is on tonight) & Garfield's Xmas special (which I haven't seen in forever).
More grown-up Xmas movies I like include Elf, The Man Who Came to Dinner, & even It's a Wonderful Life (or as it's known in Italy, Itsa Magnifico Life!). But man, as a kid I abhorred IaWL. @ the time, it was public domain, so Public Television played it constantly. Then they found out some of the music was still under copy protection, so the big networks got a piece of the action.
Frosty the Snowman, Rudolph, The Grinch, Home Alone, The Santa Clause, The Muppets Christmas Carrol. Okay, so a couple of those may not be long enough to qualify as a movie, but blah.