It would help to know what camera you used. However, more helpful would be a sample picture. I suspect your pictures are underexposed and/or blurry. You can use photo editing software to improve the quality slightly, but if the images are too dark, ... sorry.
I recommend PhotoShop Elements 2 or 3 or Paint Shop Pro 8 or 9. The earlier version of either program can be bought cheaply on Ebay. Other cheaper programs can do basic image enhancement.