You have to admit, the list has a pretty wide range, from creatures new (the minotaur from the just released Prince Caspian) and old (the original King Kong). I guess Jabba the Hutt is a fair choice from the Star Wars universe, but I would have chosen Yoda because he's a richer and more complex character and he has a lot more screen time throughout the entire series. I'm pleased to see two Harryhausen creations, the skeletons from Jason and the Argonauts and Medusa from Clash of the Titans, among the others. I suspect that Smaug from the upcoming The Hobbit will replace the dragon from Eragon.
The only creature I find truly frightening is the Pale Man from Pan's Labyrinth. See what I mean?