First timer here. I bought a used G4 MDD 1.25 dual FW800 recently. Was pre-loaded with 10.5.6. I thought that I would add a hard drive. After attempting to format, it rebooted to a gray screen with a MacMonitor icon. If I hit "option", I can get it to progress to a blue screen w/ padlock asking for a password. I only remember setting a user password. I believe this is asking for an admin password. So, I thought that I'd get the 10.5.6 Install disk to reset the password. I can't seem to boot from the Install disk! I've tried holding down the "c" key at startup, (also the "option" key). No avail. Completely frustrated!!!