i clicked the line top right that said search and got a google search, typed rescue win as searchwords. checked www.knoppix.net and hit search, got 3 hits. this link should help i think.
http://www.knoppix.net/wiki/Rescue_FAQ
if not search with other words you think might help.

if you tell us more what seems to be the problem we might be able to be more specific.
As it is now we have to teach you EVERYTING that could possibly be done to a disk (in knoppix/linux) to cover all the posibilities, a few months of full time studies at minimum, and in the end it might be a simple thing that takes 1 min to do, or be a total waste of time (disk is "wiped" and in need of skilled engineer with electron microscope and years of work to recover)