Python would probably be of the most use to you outside of making games, assuming it's used in 3D apps for making scripts, especially for Maya, Modo, and Blender. The problem is that Python isn't directly available in Unity, the closest thing is Boo. Were you to learn Python, I'm not sure exactly how much of that knowledge…
The short answer is yes, though in many ways it's much more roundabout to get a game working in Actionscript than Unity. You're basically starting from scratch and building up a game from there, though you don't have to go as low level as something like C++. Most of the really complicated things are taken care of for you…