ovoon: So for the guy that said Ninja Scroll, Ghost in The Shell and Akira are the only good anime with few exception... you're full of crap. The difference is that I've watched hundreds upon hundreds hours more anime than you. Also, what made it to the US I've found to be lacking.
There's a certain amount of subjectivity involved. In "that guy's" defense, there are a certain amount of things you have to accept at face value to really enjoy anime (e.g. Japanese cultural references, differences in linguistic constructions). For some people, it's just not something they can get over - which is in no way reflective on their tastes in entertainment.
FWIW, I always thought those three anime were grossly overrated, IMO. Akira was good, but not excellent, GITS, while also entertaining, wasn't as satisfying for me as SAC/SAC: 2nd GIG, or GITS2 (which actually to me was the better film). And frankly, I think people just loved Ninja Scroll because of the graphic sex and violence.
anything by Studio Ghibli
I think Spirited Away, Princess Mononoke and Nausicaa of The Valley of the Wind are the ones to watch (especially Nausicaa, which is in my personal top five anime). Some of their other work like Howl's Moving Castle and Kiki's Delivery Service are enjoyable if you go into them understanding what their core audience is likely going to be.
keeveek: Like for example Neon Genesis Evangelion - after seeing this, there's no reason to watch any other mecha anime - none of them is nearly as good as Eva.
Evangelion? That's one of the hardest series to get into, especially if you've been raised on "Western-style" Sci-Fi. I watched a bit of the series, but got heavily into the manga, and understood immediately why Shinji Ikari is one of the most loathed protagonists in popular anime. The Evangelion reboot series is pretty enjoyable though, but again, that depends on how much pseudo-Christian/spiritual allegory BS you're willing to put up with.
Macross Plus (the OVA, not the movie) is a fantastic mecha anime to watch, and Macross Zero is also awesome (the introductory dogfighting scenes involving MiG-29's, F-14's and the very first Variable Fighter is a great opening sequence). Macross Frontier is pretty entertaining too, if you're willing to put up with all of the usual anime tropes (which Evangelion also exploits in spades). Hell, Gundam Wing/Seed weren't so bad if you ignored their blatant overuse of anime tropes too. rahXephon and Escaflowne were good too, from what I've seen of them (But apparently the NA version of the latter and the movie were awful).
Personally my two favorite pieces of mecha anime were Patlabor and Patlabor 2; both really thoughtful in their presentation, and the best depiction of "realistic" mecha that I've seen so far.