How can I remove virtual desktop from Debian?

Top Page
Attachments:
Message as email
+ (text/plain)
Delete this message
Reply to this message
Author: Mark Berkwitt
Date:  
Subject: How can I remove virtual desktop from Debian?
I have Debian configured for three resolutions:
640x480, 800x600 and 1024x768.

However when I go to play games my mouse can sweep out beyond the desktop
uncentering the window. How can I remove this?