Newbie video problems

[Hal Davis]

I grew up in DOS and Windows, but just getting started in Linux. 
Installed Ubuntu 7.10, and had it set up a partition on my Windows laptop.

First, I don't know how to interrupt the boot process to tell it to load 
Windows instead of Unix.

Second, the Linux install didn't work until it reloaded using Video Safe 
Mode (or something like that). Then, noticed that the bottom of my 
screen wasn't being displayed, so if I moved the toolbar to the bottom, 
I couldn't see it (but I was able to move the mouse down all the way, 
right click, and access properties to move it somewhere else). Then, 
like a genius, I thought I'd change the video selection to solve the 
problem. I guess I was expecting the Windows-like temporary 
installation, that requires me to tell it that it works before it's 
really switched. But now, I can't read ANYTHING on the screen after the 
initial Ubuntu logo.

Tried to figure out how to change the video (went online and looked at 
help), and it gave me some scripts to run. Problem is, I don't know how 
to run the scripts. The only DOS-like prompt I've been able to reach is 
GRUB> and it doesn't like the text I input. I'm guessing that if I knew 
how to get to the correct prompt the scripts would work fine.

Can someone tell me how to get my Linux system out of the ditch?

Thanks,

Hal Davis