We use Photo Gallery to edit our pictures; it's quick, does everything we need, and—best of all—it's free.
For example, I really like this shot but it's crooked and a little washed out. To get started, I just double-click the photo. I’m automatically on the Edit tab and can see all of my options at the top.
You can edit your photos on the Edit tab in Photo Gallery
I'm pretty lazy and tend to default to the magical Auto adjust, which fixes everything automatically. My husband, on the other hand, likes to labor over each shot and adjust them manually. When he's feeling particularly artistic, he'll crop them and choose interesting effects, like black and white or sepia tone. No matter how much—or how little—you change, all your changes are automatically saved. (You can change your mind later on by opening the photo and clicking Revert to original.)
With just a few quick adjustments you can dramatically improve your pictures