I dont believe the bible - BUT treating it as a work of fiction as i would The Lord Of The Rings or something like that... he definitely IS NOT the Archangel Michael. Anthony Buzzard is very good at proving that. I find the Jesus being God idea to be contradictory. For every "proof" a trinitarian gives me i can give another proof showing that he cant be. I think the original teaching was that he wasn't god, but as the Jesus cult grew people started making bigger claims as they got carried away. Next thing you know people think he actually was god.
As for his per-existance... i'd say no. If i were reading the story for the first time without any preconceived ideas i think it's clear that he was a man who became divine. And that the example is that we all can be divine too if we copy him.