What is the best animation method for blender?

I was wanting to use Rigify because i hear it was very simple to use,
and the game engine im using (Unity) supports Rigify also.

Any ideas?

I was wanting to use Rigify, But as far as i know it only works for 2.5
I have blender 2.61 and 2.63,
It auto runs blender 2.61 and Rigify doesn't load when i install the addon
Because it errors, Also how do you switch between Blender versions?