small problemo with screen resolution

I loaded Knoppix (Debian) on my new Dell PC. Everything went ok...although it looked like my screen resolution was set a bit low. I went to the terminal and typed in the new screen resolution. Apon re-booting, I get a bunch of squiggly lines on my monitor. Now obviously I can not see to "get back in" to change the resolution back. When I re-boot, I hit "E" and get the GRUB> prompt. How can I get back to root to type in origional screen settings. I can still boot and run knoppix off of the dvd....but when I change the settings in the terminal window there... I guess it does not "remember" the setting so when I re-boot I am back to squigly lines.

Any help would be appreciated. I have a 19 inch digital flat screen monitor and sure would like to be able to use it at the higher resoltions....

Sorry for such a N00B question...but I'm kinda excited and really want to get Knoppix (Debian) back upand running as it is the first distro out of like 10....that actually did WORK (for a while Smile on my pooter.

boot knoppix CD/DVD
mount the "/" partition of your knoppix install
change the /mnt/knoppixpartition/etc/X11/Xorg.conf or /etc/X11/Xfree86.conf (depending on distribution) text file as you require.
type sync and hit enter
unmount the partition
shutdown Knoppix
when you now reboot you should have the corect settings.

OR

you could type something like "knoppix init=1" in the grub console, do the changes and type init=5 to get regular X-login.