How do I modify protected files with Knoppix?
 

I need to modify the menu.lst file of my installation of UBUNTU (which currently freezes on boot up). How can I modify the file with Knoppix? I need to become a superuser (which I understand UBUNTU is a little different than other distributions) and understand how to find, open, modify and save the file. Any suggestions??

I think that you can use the kdesu program to run kate and edit it that way. If not, you can use a console based editor such as vim or emacs: sudo vim /boot/grub/menu.lst or sudo emacs /boot/grub/menu.lst.

If you which to learn the fundamentals of using vim, there is a program called vimtuter.