What PP software? Summary anywhere?

Does anyone know of or have a link to a brief overview of the differences/strengths etc of the different postprocessing software options available nowadays? I am a little confused as to what would be best for me...

E.g. Photoshop/Elements/Lightroom/Anything else

I think I can get Lightroom almost for the same price as Elements, since I work in education, but don't really know which would be a better choice.