[G4] Re iMovie 6 HD help

[Robert C. Buitron]

I'm posting this question in various places hoping that I'll get an 
answer to solve my problem.

I have a G4 dual 1.25 MD, 400/800 firewire with several internal HDs 
that have lots of available space.

I converted a 30 min. VHS tape to digital using an ADVC-100 converter 
(which I have used in the past and no problem).

I have iMovie 6HD. FYI: I have converted other VHS tapes in the past 
using older versions of iMovie without a problem. I have iDVD v.8 but 
did not install iMovie 8.

The conversion was successful and I can view it in iMovie. However I 
want to view it as a Quicktime readable file (as I want to copy this 
movie to my classroom computer for student viewing). When I choose 
Export or Share>Quicktime everything follows accordingly until I get 
this error message regarding Quicktime and the designated HD (I have 
attached an image below). I tried Export to iDVD and CD-ROM also without 
success (get a different error message).

The error message reads: "The movie could not be sent to QuickTime, 
because of an unknown error. Please make sure that your project disk has 
write permission and that you have enough disk space (Error-54)"

The file exists and I can view it in iMovie but that's it.

What steps have I missed; what do I need to turn on/off; and is there 
another way to do this?

Thanks for your help and any suggestions.

Rob