I tend to like Kurosawa's more flawed work, like Ikiru, Red Beard or Dersu Uzala. They strike me as his most humanistic films.
Dersu Uzala is one of his best films, I've said it until I'm blue in the face, but it's rare that anyone agrees with me. It's not Kurosawa most accessible film, because of its plot and structure, but its thematics were deeply important to him -- Kurosawa's love for nature and the noble spirit of Dersu Uzala, and his persistent struggle between humanism & friendship and the belief that human nature is easily corruptible. A beautiful film about friendship, which leads inadvertently to one of the great tragedies in Kurosawa's cinema.
I also love the final dream in Dreams, with Chishu Ryu.