I'm going to start with a very strong recommendation:
Onibaba (1964)
I stumbled across this creepy little flick earlier this year and was stunned at how shocking and grotesque yet quiet and subtle it is. It essentially revolves around three very different Japanese peasants and the horror that befalls them as soon as lust and jealousy enter their lives. It starts out slowly but by the end I felt so disturbed and enthralled that I watched it again that very same night.
I think what's really wonderful about it is that it really is a time capsule; it transports you back to a time long ago and tells its story in the same fashion- it's a moving folktale.
Highly recommended, and definately essential.