You know what has worked for me really well on windows.
My Computer > Properties > Advanced System Settings > Environment Variables >
Just add the path as C:\Python27 (or wherever you installed python)
Then under system variables I create a new Variable called PythonPath. In this variable I have C:\Python27\Lib;C:\Python27\DLLs;C:\Python27\Lib\lib-tk;C:\other-folders-on-the-path