The Disney release is the long version. There had been a previous release by New World films in the 80s which cut everything fron the story which wasn't death and violence, which created a misleading storyline and a even more misleading poster
Can you spot the only character on the poster who actually appeared in the movie?
Yes it's Princess Zandra, in the upper right.
Miyazaki was somewhat miffed by this version, and when Disney wanted to release it, he said "No cuts" - every frame had to be retained.
Ironically by this time he had actually abandoned the environazi message of the cut scenes which had so impressed the WWF back in 84, and as the story developed in the manga it turned out the the whole backstory as presented in the anime (blue clad messiah prophesised to lead humanity to a naturally healed Earth) was a lie.
THE END OF NAUSICAA by Marc Hairston WARNING link contains spoilers to the manga)And that's a massive understatement - basically whatever Nausicaa decides to do will result in genocide. "probably shouldn't have said that." < /Hagrid>Marc: I'll go fast. Rush, rush! Now that you've seen the movie, I want to tell you a bit about how the manga ends. I won't go all the way to the very end, I don't want this to be a complete spoiler, but I want to show you how Miyazaki worked out some of the themes and conflicts. As you know, you've only read the first quarter of the whole story. It took him almost 14 years to write the whole thing. And over the period, the story changed as Miyazaki himself changed. He started out as a leftist as young man (well before he started working on Nausicaa), a Marxist, someone who believed that, with the proper social conditions, humanity could achieve a perfectly peaceful and just society. Some of that idealism was still in him when he started the manga. But his opinions changed overthis time. Ironically, given the current war in Kosovo [remember this lecture was done just after the NATO attack began in March 1999], one of the major influences on him was watching the old Yugoslavian republic, which had supposedly transcended the racial and ethnic hatreds, descend back into sectarian fighting as the country disintegrated. So the story in the manga took on a darker and more morally ambiguous tone.
And it's the view of a imperfect world, with the works of mankind being as natural as "unspoiled nature" that is behind Miyazaki's later works like Mononoke, Spirited Away, & Ponyo.
That said Miyazaki's demand that the original Nausicca be uncut is artistically correct. It's still his masterpiece, with all the features that cahracterize his work present.