I have a Christian faith question?

Don't get me wrong, I am a believer of God, but I've recently gone into a faith crisis. I have to wonder...did God purposely choose or know who was going to be saved from eternal death before he created the Earth? If so, what would be the purpose of creating us---why would He need to be glorified if He already knew who He was? He's a creator, but at the same time, it doesn't make sense (maybe just in my little human brain) that He would know everything that was going to happen in our lives before we did; that He knew we had a purpose of his deciding before we knew, etc. I know, I should read the Bible for this answer. Did He know the people that would rebel against Him before He created them?? Did He only choose a few to be saved in order to fully display His character to those at His mercy? If so, how does free will fit into that? Does He see all possibilities then leave it up to us to choose? At the same, since He's all knowing, wouldn't He already know what path we were going to choose since He knew our characters and our flaws? Bible verses would be helpful....