OK, I've only had a live knoppix disk for about 2 weeks (no Linux experience at all), but this may do the trick ...
IF your laptop has both a floppy and cd rom drive accessable simultainiously you should be able to boot from the floppy drive which will (in turn) find your cd rom at boot-up and load Knoppix as usual.
I made the boot-floppy on a Windows PC as follows:
- Place the Knoppix cd in your already running Win-PC and an empty, formatted floppy into thier respective drives.
Open a DOS Box and and change directory to your cd rom drive. Then "cd" to the knoppix directory. The prompt should now be D:/knoppix (assuming "D" is the cd rom drive).
At that prompt, typ the following: mkfloppy.bat - and hit enter.
Now you place both that floppy and the Knoppix cd into your Laptop and re-boot. I did this successfully on my main PC in order to use the 2nd, non-bootable CD-RW drive to to load Knoppix. Hope this works for you. Good luck.