Well, I've only seen 1984, which was absolutely dreadful and nowhere near as good as the novel it was based on. I never really thought the adapters got Orwell's main points and certainly never conveyed them very well if they did.
V is based on an Alan Moore story and those never live up to what they should be, so that's bound to be bad, too. Dreadful casting decisions don't help here, either (What's Natalie Portman doing in a world where all the Jews have been killed?!?)
Hmmm... I think I'll have to go with V as the 'best', though, having seen and really disliked 1984. V can't be worse! ;D
I never saw 1984, so I'll go with V by default since I've actually seen it.
That said, V wasn't really that bad of an adaptation overall. They took some liberties with it, but overall it followed the basic structure of the book. It's not nearly as good as the book, but still much better than the vast majority of Moore adaptations. Of course, given that Snyder ruined the ending of Watchmen and the others are even worse, that really is not a compliment.
Thinking on it, comparing Moore adaptation films could be interesting. In a migraine-inducing sort of way. ;D
I've seen V for Vandetta and cannot remember a thing about it. I've read 1984 and loved it, but I've not seen the movie. I won't be surprised if the movie is bad. I'm going to have to abstain from voting on this one.