I have a MacG4 flat panel that has been a great computer for years. I recently bought a new machine and wanted to give the old one to my niece. I went through the disc, getting rid of files to clean it up and then optimized the disc with an old Norton Utilities disc. From then on I could not start-up the disc. Reset pram, tried safeboot. It won't start up off original start-up disc either. The only thing that starts it is Disk Warrior, which tells me No System Folder was found. How can I reload the system if I can't start this up with the install disc?