Best anime ever: the only anime worth watching, I give new anime a two episode chance and usually forget they exist afterwards, these are the only anime I watch, believe in, and love: everything else is crap
A Little Princess Sara, anyway you can find it..!
Sailor Moon, in its original Japanese [the BEST ever]
Pokemon, dubbed: an absolute classic [one day people will admit it]
Fullmetal Alchemist, in its original Japanese [only new anime worth watching]
Neon Genesis Evangelion, in its original Japanese [there's a reason why it is what it is]
Revolutionary Girl Utena, in its original Japanese [Junichi Sato is a god]
Avatar the Last Airbender [yes, it's anime, and yes, it's better than everything sans Fullmetal made in the past 5 years.
Honorable Mentions:
Slayers [FUNNY!]
Blue Seed [under rated!]
Kimagure Orange Road [classic]
Dragon Ball Z, in its original Japanese [half your favorite games, anime, manga, would not exist if not for DBZ]
Ranma 1/2 [Takahashi's only great work...!]