I recently loaded OS 10.3.4 on an iMac G4 with OS 10.2.8. I completed loading disk 2 successfully and upon trying to load disc 3 I found my mouse not working and the Finder not responding. I am able to see all my files and the dock, but unable to do much of anything else. I have tried to force quit the finder and it relaunches over and over to no avail. I unplugged the keyboard, mouse, and the actual monitor. Nothing. Is there anything else I can try. And if not, what is my next step?