Hey Mark,
For dings, you're best off taking the car to a PDR (paintless dent repair) place. Those are impossible to fix yourself, unless you're skilled with PDR.
Scratches (small ones) can generally be touched up, but it shouldn't look like what you're describing. You might want to get out Dr. Colorchip (
http://www.drcolorchip.com) - many users here have had success with their method and products.
This thread also has some good information:
http://www.e90post.com/forums/showthread.php?t=282485
