For those of you who don't have the software or skills, here's a cool, easy-to-use, FREE tool that you can download off the Web - you can use it to resize, crop, and up contrasts (all the basic requirements, like; you can even add a watermark saying, e.g. "Copyright Joe Bloggs 2008"). You can allso do it to whole folders at a time!
http://www.snapfiles.com/get/webresizer.html