Kenshin OAV is awesome. It's really pretty deep, has great animation. The story is fantastic and opens the realm of Kenshin's past (which is kinda nice if you started watching the series first). I like the series so far too, but have only seen up to ep 31. I hear that the next 30 or whatever episodes are much closer to the manga, and much better on plot. (not that they were bad in the first place
Another good movie is Princess Mononoke. I think what I like most about it is that there is any "good guy" or "bad guy" (other than Ashitaka who'd be good by way of representing the side of compassion). You'll see that all the characters in the movie are simply trying to exist, and fight for what they believe. (Much like the Kenshin OAVs)
So I highly recommend those two animes. I you want to be mind-fV#ed. Then watch something like EVA (episodes higher than 15) or Lain. You should also watch Akira, it's like a requirment for any anime fan, IMHO.
Cheers