A Christmas Carol last year. From the very first paragraph I knew I was in for a treat of understated witticisms and vivid descriptions. I fell in love with Mrs. Cratchitt in an instant when I heard her described as wearing "a twice-turned gown, brave with ribbons." How can you convey that sentence in a film?!
I also heartily recommend, "Conscience Pudding" by E. Nesbit which is one of several Christmas short stories put out by Librivox. As always, you get a mixed bag when you have volunteer readers, but "Conscience Pudding" was excellent. (It's the eighth story as you scroll down the page.)
Honestly, half of the enjoyment of these stories comes from the British voices reading them. If you're too busy to read this season, put a few of these on your iPod and listen while baking or wrapping gifts. Enjoy!