I tried to install bootcamp and I ran into a little bit of a problem. I aborted the install because I thought the partition was messed up, now when I boot the computer I just get the grey screen. When I hold down the option button on startup it does not allow me to choose the operating system. How do I get my Mac OS back? I never installed Windows XP, I never formated any partition. I have everything backed up so if I have to reinstall it is no big deal. How do I boot from my installation DVD? Please help!!!