I have a iMac g4 running tiger(10.4.11) and I can’t get it to run leopard. I’ve tried everything: booting from usb solicits an error message that I have to force shutdown my computer. It doesn’t read the dvd and simply ejects it. I even tried partitioning the disk and mounting one partition as the installer, still, no luck. I can get it to boot from a usb drive with the Tiger installer and it works just fine. Please help!