There are a few free picture programs which you can download which will greatly help you manage your photographs.
These programs have many features which will allow you to organize and fix minor problems with your photographs. I recommend Picasa, GIMP, Photoscape, and Windows Live photo gallery. All of these programs can easily be found on the internet. Below I will give you a brief description of each program.
Picasa A very user friendly program which allows basic picture manipulation. You can crop, resize, organize, watermark, and use one of the many manipulation functions to adjust color, sharpness and contrast. There are a number of additional features to Picasa making this one of my top picks.
Photoscape This is one of the newer picture programs and it performs many of the same features as Picasa along with a screen capture program, batch editor, animated gif creator, raw image converter, picture splitter and a batch editor.
Windows Live Essentials Again, this program performs many of the same features as do the others, but one very special addition to this program is the panorama maker. This is one of the very few free programs that will allow you to combine multiple pictures into one large panorama and the nicest thing of all is that the program makes the panoramas with very little user intervention.
GIMP By far the most comprehensive program and it very closely mimics Adobe Photoshop. To get the most that this program has to offer you'll need to spend time learning the program, but once you do it will be perhaps the most valuable asset to your picture adjustment programs.