Changing themes in Windows 7 is a doddle. Get to your desktop by clicking the Show Desktop button on the far right of your taskbar.
Now find a blank space on your desktop that isn’t occupied by an icon and right click on it. Select Personalise.
The panel displays all the themes that you can choose from. Click on one to select it and it will be applied immediately.
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Changing the theme in Windows 7 changes the desktop background, window colour, sounds and screen saver all at once.
Find out what a theme in Windows 7 is.