I *love* Princess Mononoke. I think it's a fabulous film, and it says quite a lot about feminism and ecology, as well as about mythology. I don't know much about the Japanese culture the myths are based on, but the film does work well with Western myths of wilderness, and of operating within nature rather than against it.
Here's some more about the film: http://lavender.fortunecity.com/attenborough/487/

I must say that the newer Miazaki film - the more recent one (something about a journey, I'm blocking out on the name), though sweet, was a bit of a disappointment after this one.

Wow! Thanks, Yarden!