I have a Macbook that I bought in 2008 and am currently running Tiger, 10.4.11 and I am trying to install Snow Leopard with no success. I insert the CD, does not load or show up on the desktop. I tried to restart the comp while holding down C and nothing happens. I have been reading about firmware and I am not sure if I need to update that? I bought the mac box set if that helps. Any ideas???