[ale] Changing screen resolution

[ringo]

I finally got SUSE 9.2 running on my Dell laptop, but the screen is in
640x 480 mode. If I right click on the screen (KDE) and go in and change
the resolution to 600x 800 or something else then when I apply it the
screen gets all weird. There are 2 "start menu" bars, the mouse pointer
is a large fuzzy box etc. I did "refresh desktop" but that didn't help.
I thought maybe re-booting would clear it up but it just goes back to
640x480. Am I missing a driver or something? How do I get it to go to a
higher resolution correctly and stay there?
Thanks
Ringo