X window too big

[MrHobbit420]

thanks for all the help with the mouse and video card 
configuration.
 
 In the default screen I got after installing debian2.2r2, the screen is 
huge. Actually it is just
four times the size of my monitor screen and I have to 
move around the whole X screen using the mouse. So 
when I open a new window, I have to look around the 
other 3/4 of the screen to see where it opened. 
Any idea why this happened and how to rectify. 
thanks.
   nitai