I think that you should compare the old configuration file menu.lst and the new one grub.cfg concerning the boot parameters for Knoppix.

You can find many web pages with tutorials about the configuration of GRUB 2. I think that "GRUB 2 bootloader - Full tutorial" could be a good place to start.

If you still have problems then I would suggest that you show us the content of the configuration file grub.cfg and give a detailed description of where your Windows partition resides (drive number and partition number).

I hope this helps.