Hmm as it seems that some people got some problems to use python plugins with GIMP with windows I'll provide a short HowTo.
What do you need?
- Download and install Python. GIMP doesnt work with Python 3 nor with the latest Python 2 release (2.7). You need to download Python 2.6.6 *Link to source* - grab the MSI Windows Installer you need - either 32 or 64 bit version.
- Now you need install the PyGTK package. There is a complete all-in-one installer avaible at the project page. *Link to source* - grab the pygtk-all-in-one-2.24.0.win32-py2.6.msi file.
Afterwards reinstall GIMP and be sure to do either a full installation or a custom installation with activated Python elements. If the GIMP installer did grey out the python elements at least one of the above programs aint correctly installed.
Now GIMP is ready to use python plugins. In order to use them you just have to copy them into your plugin folder, which is normally located at C:\Documents and Settings\<Your windows user>\gimp-2.4\plug-ins. If it aint there you can check in GIMP where your custom plugins folder is located at.
I hope this short HowTo helps
EDIT: I updated the links.