My friend gave me a free Mac. It's in very good condition and is only a few years old. It's a Mac G4, so the software needs updating. It currently has Mac OS X Jaguar. I got the new Mac Box Set (which incudes OS X Leopard, iLife '09, and iWork '09) for my birthday and that night I tried to install it. But for some reason the disc would just eject itself. I tried what felt like forty times and I'm very new to Macs so I don't know what to do. Coulsd someone please help? Thanks!