There isn’t a way to crop a picture in Design (not in the traditional sense, anyway), but you can get the effect by using a clipping path. In Design, version 2, you can use a slice to select only the portion of the image you want, save the slice and then import the results back into Design.

[http://social.expression.microsoft.com/Forums/en-US/design/thread/76155c67-652a-405d-9b07-983d99c936cd]