Peter,

>I want to capture the contents of the Desktop (entire screen) and save it in a format which takes a small amount of space.

What you need is a screen grabber. There is one included with Microsoft's free HTML Help Workshop. It is included in some versions of Windows, and for others you can download it for free from microsoft.com. There are various other shareware and free screen grabbers available on the Internet.

If you want screen shots of your desktop, and your desktop is not a photograph, do not save it as a .jpg file. You will have a much sharper image if you save it as a .gif, .png, or compressed .tif. The amount of compression you get with these formats will depend on how many colors are on your screen.

Hope this helps,
David