Just like favorite Christmas music, lots of people have a special holiday show that they have to watch each year before they can say they've had Christmas. I'm one of those people. I used to watch them for me. Now I make sure that I watch them with the kids. Rankin & Bass's version of Rudolph The Rednosed Reindeer is one of those classics. The new one that I have to watch every year is "Elf" with Will Ferrell. But just what is it that makes a holiday special a classic?