secret wars -- first ever "event" or major crossover, from way back in '84. guessing its still in print but just look on ebay. spidey gets his symbiote costume (turns into venom), colossus cheats on kitty, every hero dies but is reborn (all in 1 story), molecule man and doc doom become all powerful, first appearance of the beyonder, hulk holds up a mountain, examples of y cap america is so great, ben grimm turns human again. loadsa stuff came from it basically. its really quite an amzing bit of superhero marvel work.
Im a big fan of powers, so would recommend the hardcover volume 1 of that, printed by Marvel Icon. its a creator owned brian michael bendis book not set within the marvel universe, but technically is a marvel book at the mo.
um... ultimates is for a modern reimaginaing of classic characters. i only have ultimates 1 #1 but i know it kicks ass! cap rrrrrules! im a spidey fan mind and so if u wana get into him just look for some old silver age tpbs, tho i just bought the far more modern (and hence controversial) "life and death of spiders".
ohhhhh, i know. get "toxin" about a symbiote super hero. ties in with spider-man, venom, carnage and new avengers and got rave reviews. i just bought that mini-series too. y else wud i b plugging it? duh. lol