I'm having the same problem with some DivX movies. Crouching tiger being one of them.
Other than the 30fps point this seems to happen mostly with either "large" picture size movies(640x480) or "small" (~400x300).
I have tried several other players besides WMP but no luck.
Any ideas?
(Incidently, I have tried these movies on several friends' computers and they work fine)

P.S. Is there any way to uninstall all codecs? (I don't want to have to reinstall windows just to reinstall some codecs!...)