If you like Bleach, D.Gray Man is a must. I have to say, I am absolutely hooked. Its like Bleach before it got crappy
As I said, Gantz is very addictive, and a bloody/magical/superpower older one to catch is Bastard. Though be warned, watch it subbed. The dubs had me crying with laughter...
If you haven't yet seen Akira and Neon Genesis Evangelion, they are old school anime that took most people's anime cherry
H.