Hi Frank Lee, thanks for your reply
The drive itself isn't corrupted, it's something else we haven't even figured out yet. Running chkdsk on it was one of the first things I did and it always shows the drive as being fine, when I can access the drive at all. Something's off either with the firmware or a piece of hardware inside the machine has frazzled and only occasionally works.
You are a lucky charm though because when I booted up my pc this morning I have access to the drives on my ereader, I will follow Mark's instructions above.