If they are getting distorted, then it could be that Windows is stretching the image to fit the screen (this is of course only if you are using windows).
If you are and like a particular image and want to correct it, then right click on your desktop and select Properties from the pop-up menu. This will open the Display Properties window, then click on the upper tab labeled Desktop. Here you will see options for the image you have saved as your desktop on the right side. If the right side menu says Stretch, then you can set it to Center and that will remove the distortion.
Thanks to ALL! I found a GREAT ONE!
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