I tried installing XP, it didn't work for some reason. And now I have difficulty installing Vista too. I have both original discs. I rebooted the computer from the Vista disc and I came to the screen where it didn't allow me to install Vista on any of the partitions listed and instead asked me to load a driver which I assume is the Mac OS X disc, but I cannot eject the Vista disc in order to insert the OS X. Anybody can please help out a noob? Thanks again.