I finally saw Hero this weekend. The way they told the story was really cool, and it was very beautifully filmed.
Iron Monkey is my very favorite movie ever.
I agree with all of moe.ron's list and off the top of my head I would add:
Once Upon a Time in China II (better than the first IMO but both are great)
Fist of Legend
The Legend
Drunken Master
Kung Fu Cult Cinema is a great resource for kung fu.