I subscrebe to a newsletter called WindowsSecrets, this week they have a story:
Free photo-editing tools do more than ever
By Lincoln Spector
When digital photos need fixing, having the right tools at hand — and knowing how to use them — can make the process fun and pleasing.
If you're not inclined to spend much on a photo editor, the latest free editing apps provide some surprisingly powerful tools.
*Here are acouple they mention:
Paint.net: Getting down to business
It's amazing what can be fit into a small package. Once installed (download page), Paint.net takes up only about 20MB of disk space. Yet the application is a surprisingly powerful and versatile image-editing tool.
FotoFlexer: Have fun while you fix your photos
If your goal is quick photo fixes, or you don't want to install another program, FotoFlexer is worth a try. This Cloud-based service, financed with advertising (which is only occasionally annoying), offers a significant set of photo manipulation tools. And it's exceptionally easy to use.