Attached Link: http://www.renderosity.com/tut.ez?Form.ViewPages=131

You could resize the entire image if you want to, or crop one part of the image, resize that to 200 x 200 and use that as a thumbnail. Most people tend to use just one part of their image as the thumbnail. Here is a link to a tutorial on resizing your images for the web which might help. Shoshanna :-)