KH = carbonic hardness. It is a measure of alkalinity, that is the ability for your water to neutralize acid. Reasonably high KH is good, as it will help your tank resist pH swings.
GH = General hardness. This is a measure of pretty much Ca+ and Mg+ (calcium and magnesium ions) in your water. It includes other ions as well, but these are the main components. It is what folks are talking about when they have "soft" or "Hard" water.
Based on your measurements, I would say you have very low KH, and medium to medium hard water. If you have issues with pH swings in your tank, you can increase the buffering capacity of your water by either adding sodium bicarbonate, or even by adding an airstone to add turbulence which will gas off as much CO2 as possible. Of course, with a planted tank, this would not be a good thing. If you are not having issues, than I would leave it alone.
