My thoughts on the ending
To anyone who feels that the altered endings of this film and the more recent one from 1999 "destroy the entire spirit of Orwell's novel," I say phooey. Both movies make all the same points as the book does and use the same symbolism, they just end differently. I really don't understand why everyone is getting upset over this one little fact.
The book's ending is anticlimactic, this is undeniable. You can argue about the meaning and the symbolism of the story until your voice gives out, but it doesn't change the fact that the ending of the book would make for a lousy, unsatisfying ending to a feature-length film. Books and movies don't work the same. End of story.
What makes getting worked up over the changed endings even more bizarre to me, is that both of the "new" endings are not only entirely believable, the '99 film moreso than the '54 one, but also could work as logical outcomes of the situation. I mean, oppressive totalitarian regimes like the one headed by Napoleon always come crashing down in some form or fashion, don't they?
Because terror tactics and strongarming the populace will only work for so long, eventually, something gives. Either the people can't take any more and revolt, as they do in the '54 film, or the regime basically collapses under its own bloated weight after so many years, as we see in the '99 film. The only reason the ending of the '54 film is not as believable as the other one's is that the revolt happens too suddenly, and too soon.
And both endings are still pretty dark, and only "happy" in the sense that the bad guy gets his just desserts. Because even though the pigs are overthrown in one way or another, the damage they've done remains, and the surviving animals will have to pick up the pieces and rebuild. Both endings are just as open-ended as the book's, if you think about it in this context.