Thanks everybody for replying. I am quite fortunate to have a Lacie drive as well which I have just deleted lots of media on, so I will copy the media on to the Lacie drive and format the other drives.
I have one other question though.Why is it important that I reformat the drives to Mac OS X extended rather than Journalled? My other 2 drives that work properly are formatted Mac OS X Journalled, could you tell me the difference?
Thanks again
Dave