Need help

Hello, I just registered today. I'm trying to dual boot windows 7 and snow leapord. The problem that I am getting is, that when I try to boot into Mac, it just shows me the logo and then keep restarting endlessly. I keep restarting it and keep on getting the same thing. I'll start from the beginning on how I started off. Maybe you guys can find out something I missed or did wrong. First I put in snow leapard cd then when the installer loaded i went into utilities, then disk utilities. I then split my hard drive into two partions. First one i named Snow Leapord the second windows 7. Then after it erased everything and partioned I installed snow leapord on partion 1 then windows 7 on partion 2. When I chose Mac it gave me the problem that I mentioned above. So right now I'm on the second partion the one named Windows 7. , because I want to use Mac badly!