Out of curiousity do you have a SCSI drive? Do you also have Classic environment installed (such as OS 9)? Your G3 was around the 600 MHz right? The last official G3 was 450 MHz but I recall there was an option to speed them up beyond this. I can't remember how ... unless it was turning the clock up or something.
My My I'm slow typing tonight! No I was asking if you ever had reformatted your disks. I'm NOT suggesting you should.
Perhaps you should look at this:
QuickTime 7.0.4 bug stops LimeWire from opening!