My screen resoltion does not work i want to change my screen size how can i do that .is there any body help me?

my question is that i want to change my screen size of my window but when i go on my screen resolution than it doesnt move that stick to change the screen size .what should i do i need help .My screen resoltion does not work i want to change my screen size how can i do that .is there any body help me?
For Windows operating systems, the resolution can be changed from the ';Display'; option in the control panel. If you wish to change the size of just a window, then you can left click on a corner of the window and drag, which should allow you to resize (this isn't always the case, sometimes the windows are fixed). Pressing the ';maximize(square)'; and ';minimize( _ )'; buttons beside the ';close(X)'; button will also change the size: maximize will fit it to the screen size, and minimize will hide it from view. Check Microsoft's site for additional information:

http://www.microsoft.com

If you use a Mac, then check Mac's website:

http://www.apple.com