Hi Don,
am sitting in front of my beloved G5 and got the same message. In my case, it was a weird corruption in a dissolve – look for things that won’t render – I found the dissolve in a complex 24 minute show by trying to export the timeline in pieces – didn’t take long to isolate the problem – got that crazy general error message repeatedly in one spot!!
solved the problem by deleting and reapplying the dissolve – your problem could be similar….
good luck!!
Chris W