How I can modify a file on the hard disk!

[Ionut]

In my office y have a Red Hat system and i have a problem with file /etc/fstab. How i can use Knoppix to boot from CD and edit this file ( it is a root file) on the hard drive.
Thank you.
Ionut

[mzilikazi]

Mount your drive rw. There are some desktop icons that make this easy.