His stuff is kind of divided into samurai epics (*) and post-war Japanese gangster/corporate corruption pics (#). My favorites:

Ikiru(#), Ran (*), Red Beard, High and Low (#), Dreams, Throne of Blood (*),

They're just a different metabolic rate than most American films. If you can appreciate them you'll be hooked forever. Also want to recommend Ingmar Bergman, Kurosawa's contemporary and another of the world's great auteur directors.

Virgin Spring, Seventh Seal, Fanny and Alexander