Alright. So for your second question, why would He send us to hell for something so seemingly insignificant as us not believing in Him?
Tell you what, that is a great question, something that trips a lot of us up.
It does seems very unfair and harsh. But let's try looking at it from God's point of view.
God is perfect, holy, righteous, he is above the presence of sin. Therefore, we aren't allowed to be with Him in His perfect dwelling, Heaven, unless we are perfect! He cannot be in the presence of sin. Sooooo, we must be forgiven by the power of Jesus so that He is unable to see our sins any longer. Anything less than perfect deserves eternal death, because we do not meet His standards.
Romans 3:23 sums it up well. "And all have sinned and fall short of the glory of God."
Oh, and for the record, this wasn't initially God's plan. He intended for us to be perfect, so that we could always be with Him. Instead, because of Adam and Eve's disobedience, He introduced an alternate plan, where we must be forgiven first.