I know what bones animation is! If you have bones animation you can assign a skeleton to a model and rather than moving the vertices manually you can move the bones. This is really helpful for making humans and animals and probably other organic things that in real life have skeletons. I think it's easier to animate as well as to make it look real.

My opinion on which to buy is, unless you have a lot of money, the Commercial Edition. That's the one I have.