Sorry about the late response.
My computer was acting up for a couple days.
But I have to say, book two was better than the first :]
About Ivan's argument, I didn't understand the details of it, but I got the main point. He wants the church and state to be combined or he wants the church to stand higher than the state. Ivan wants to use the power of God to deter crime, but Zosima doesn't think that will work. It's weird that Ivan supports such an idea when he's an athiest.
Fyodor is an idiot. I can't believe he would put on such a show just to embarass Miousov and Alyosha. He's a horrible person and I can't imagine that he'll change before he dies.
Fyodor is indeed an idiot. I, too, was a bit confused about the church/state argument.