Latitude D600 w/external monitor

Not sure where to begin

I've been using my D600 w/ an external monitor with no issues. When I traveled, I simply unhooked the monitor and there I went.

In between my last two trips I remember fiddling with the video settings (right click on desktop - properties - settings) to increase the amount I could see on a page. I don't recall what else I did, but the next time we were away when I tried to boot up my laptop without the external monitor, the LCD screen would not show an image, except briefly at reboot before going dark. Returning home, I rehooked it back up to the external monitor and have been happlily computing away.

In anticipation of another trip, I decided to see if I could fiddle with those settings again and get the laptop's display to work.

Well, (right click on desktop - properties - settings) showed 2 monitors and I obviously shouldn't have dragged either of the little boxes around on the screen, because now my external monitor is .... how to describe this... I have the tulips and it's completely distored. There's a screenshot here:
http://img14.imageshack.us/img14/4499/eww1q.jpg
It looks like only a portion of the standard tulip background and shows only 16? 32? colors?

Worse, it doesn't display my desktop icons or the start menu, even though I know they're there, because I see them on the laptop's display for a brief moment when I reboot.

I can't figure out how to get to safe mode. If F8 is doing anything, I don't know because I can't see it.

I cannot find my Windows CD. I am hopelessly unorganized.

Can anyone help me get this working again?

Thanks!