Close or minimize all your windows, so you see only the current desktop background.

Click your RIGHT mouse button on your current background - where there are no icons - and a small menu should pop up.

Click "Properties" to show the Display Properties window.

Click "Desktop" at the top of the window to see your choices for backgrounds.

You'll see your current background highlighted. Make note of the name and whether it says "Stretch", "Tile", or "Center" in the lower right corner, just in case you want to go back to it.

You can scroll through other backgrounds stored on your computer to see if you like them, by clicking on each one.

Click the "Browse" button, find the picture you want to use, and double click it. You'll see what the desktop will look like in the mini-picture on the window.

Experiment with changing the "Position" between, Center, Tile, Stretch. If you like it, click OK to change your desktop. Otherwise, click "Cancel."

"Prairie Wind," which comes with Windows XP is a nice soothing dark color, with a little character - but not too busy - so it's easy to pick out desktop icons.

Here are more options.....

Here is another  method of changing the desktop background...

Very simply...if you see a background or picture anywhere on the web...instead of RIGHT clicking and choosing 'Save as' and sending to your pics folder...choose 'Set as Background' and it will instantly change your desktop picture!