I want to ask how can i change my screen size?

i want to change my screen resolution but when i go to screen resolution it just remain by the size of 640 by 480 pixels .it does not move right and left just remain still .how can i change it .i have tried alot but havent fix it yet .i will appreciate if somebody help me to resolve that problemI want to ask how can i change my screen size?
In Windows XP...

1. Click Start

2. Click Control Panel. If you are in Category View, switch to Classic View.

3. Click the Display Icon.

4. Click the Settings tab at the top right of the window that opens.

5. Under Screen Resolution, left click on the arrow, hold you mouse down and drag it to a different size.I want to ask how can i change my screen size?
if you have a windows 7 (and possibly vista would work as well), simply right-click on the home screen and select 'screen resolution'



:D couldn't be easier!



unless you are on XP. where i have no idea sorry!



hope this helps :)
I'm still using win 2000, for that system it's rightclicking the screen -%26gt; from the drop down list check properties at the bottom -%26gt; one of the tabs at the top of the next screen lets you change the screen resolution.