I don't have a solid answer for you. It's a matter of opinion and it derives from my relationship with God. One day I will read a story and interpret it as literally happening, and the next day I will read it and interpret it as a symbolic story. And I dont think that back-and-forth is a bad thing. I think that is what is so great about the Bible. I dont know if you are a Christian or not (forgive me, in all this discussion I have lost track), but if you are, I would think you would understand. If you arent, then sorry, this answer probably isnt making sense to you.
Going back to your "Jesus as a metaphor" proposition: If you are a Christian and want to take the entire Bible as a metaphor, fine. However, I cannot fathom a Christian believing that the life of Jesus Christ was a metaphor. He is the core figure of Christianity and his life (telling of salvation, and dying and being born again) is the core theme of Christianity. For someone to say they are a Christian, yet refuse to believe that such a personification of salvation lived is hard to imagine. The whole life of Jesus is the reason said person would call themself a Christian, and I wouldnt think they would doubt He lived. In other words, I believe you can take as symbol or metaphor everything in the Bible if you please, except the story of Jesus, in whose life and lessons is the reason you consider yourself a Christian.