The Best Are: Stray Dog, Ikiru, Rashomon, No Regrets For Our Youth, (most, but not all of) Dreams & High and Low... Rashomon & Ikiru being the best.  I don't think he ever made any bad films, though Rhapsody in August is nothing great.  I would, however, spend the extra money on good video copies or DVDs, and avoid VCDs like the plague.  By the way, this is coming from someone who never really dug Kurosawa to any great degree.  I mean, some of his movies are great, but not always my cup of tea.  You might want to get an opinion from some Kurosawa freak, too.