I love Kurosawa's movies, and have watched most of them. Seven Samurai is no doubt his #1, and Toshiro Mifune is no doubt the most badass actor in his many movies. However, my
personal favorite movie is Ikiru, and my
personal favorite Kurosawa actor is Takashi Shimura. Ikiru is one of the few movies that has ever moved me to tears.
My other favorites are Yojimbo, Red Beard, High and Low, and Rashomon.
If you're a fan of Kurosawa, I'd also recommend the movie
Harakiri. It is, in my opinion, the best non-Kurosawa movie to come out of Japan.