Look at the Analyze Gels tools i linked in my last reply and combine this with the macro recorder, or just do something similar and record your actions using the macro recorder. Once you have the core functionality you can adapt it to work on whole directories of images etc.
NanoDrop is a simple spectrophotometer that you find in most labs that do anything in molecular biology. Simply put it measures the absorbance of light in one drop of DNA solution at 260nm and calculates the concentration of DNA based on this. It can also quantify common contaminants, such as RNA. it is fast, easy to use and cheap. Agarose gels are easy to use and cheap, but far from fast