Hi

If you installed it using vmware, I suppose you can run the cd under vmware, if you can, start the cd and then open konsole and type:

Code:
#su
            #mount /dev/your partition /mnt/your partition
            #chroot /mnt/your partition
            #passwd
And type your new root password, then when you run from your hard disk. this new password would work.

Your partition is where you installed knoppix