MS Paint on steroids. If you want a photo editor that can do alot more than re-size and crop this is a good bet.
GIMP is the GNU Image Manipulation Program. It is a freely distributed piece of software for such tasks as photo retouching, image composition and image authoring. It works on many operating systems, in many languages.
While neither Gimp nor Puget Systems charges for the installation and use of this software, we do encourage you to make a donation to the developers if you find Gimp useful. You can do so by following the directions on the Gimp donation page.
Configure a quiet custom PC with the Gimp.