Thanks for the replies.
Ive used Caldera and Mandrake so am familiar with linux but I would appreciate a bit more detail of what you say. Here's what I tried:
Booted up with knoppix cd.
My knoppix is installed on hd hdc3.
I cntl-alt-f1 to root.
mount /mnt/hdc3
chroot /mnt/hdc3
login knoppix
passwd: entered password - not accepted (I know its ok - have used it repeatedly)
Tried several times, also to login to root -- times out after 60 seconds.
Am I on the right track??