anakin´s fate: lava...lava...lava...is it true?

Well, it depends what you mean. Certainly he wouldn't deliberately leave him crippled just to be mean, but anything can happen in a fight.

But he was in that fight- that assumed fight, anyway- to kill Anakin, and the gloves have to come off at that point.

It would be cool if he chops off Anakin's prosthetic arm and says "Now Anakin, I don't want to hurt you more than..." but then Anakin retaliates and tries ot kill him or something.

Could you really see Obi-Wan doing that? He's the serious sort. He would know that if it came to a fight, it was to the death.

That's the point really, I guess. It must have torn Obi-Wan apart to have to fight his best friend, but I am sure he knew when he made the decision that this wasn't going to end halfway.

Hmm...

Obi-Wan almost fights Qui-Gon in the Jedi Apprentice series. Those are good books.