Photoshop Elements is pretty cheap and easy to use. It has functions to change the brightness and contrast of photos. When your camera picks the exposure, sometimes it doesn't pick correctly, so you can fix it in the program. Their help files are pretty good and there must be dozens of books on using photoshop elements, that don't ask a person to become a power user.
Also, when you submit photos to, say "the quilt show" website, the website automatically reduces the size of your photo file to make it usable on the website. Photoshop Elements can let *you* control how your photo is downsized, to preserve maximum quality.
Kathy