Once you have settled on your theme, click on the Desktop Background option at the bottom of the Personalize window. Here you can see all the images within a particular theme and tick or untick them, removing unwanted ones from your cycle of images. You can also choose how the picture is shown on-screen, although leaving it in Fill mode will be fine unless you start using odd-shaped images. There is also a Shuffle tick box, allowing you to muddle up the order of the chosen images, so you won't know what is coming next.
Finally, you can choose how long it is until the background image changes, from mere seconds to minutes, from a couple of hours to just once a day. Click "Save changes" to commit these edits and go back to your desktop to await the next change in its visual finery.
Windows 7 finally gives the Windows desktop everything it deserves and all the features that used to be filled by third-party applications. It is easy to manage and provides endless eye-candy for the user, with the minimum of fuss and a tiny number of clicks and windows to browse through.

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