I have an ibook Power pc g4 with 1.25gig of ram and 10.3.9 os. I want to change the os to Leopard 10.5 and can get as far as clicking on the icon to install...waiting for the machine to reboot ...and that is all I do....WAIT The machine shows a spinning wheel and clunks and clicks while the disk is being read. after 20 minutes of this all goes quite but the little spinning wheel keeps spinning... Nothing else happens. I have tried to hold down the c key the option key and just did a plain old reboot with the disk in the drive...all to no avail. After looking around for quite some time I thought I would ask for help... Help?