No worries Liz, here we go.

So, Plugins (Pythons .py) goes into the main C:\Program Files\GIMP 2\lib\gimp\2.0\plug-ins
Scripts,themes,gradients,brushes etc is in C:\Program Files\GIMP 2\share\gimp\2.0\AllTheStuff
I have had problems sometimes with putting Gmic in the regular plug-ins folder, so that why i do an exception for Gmic and put them in the C:\Users\Liz\.gimp-2.8\plug-ins, besides, that folder is empty so i dont clutter up the main one.
Also, i have made a copy of my Main Gimp folder when i was happy and put that aside so when i screw up, i just uninstall Gimp and reinstall the official one in seconds.
After that i just delete the Gimp folder and replace it with my backup straight up.
Not a problem specially when you are using the same version, i'm cool with this behavior.

So, do you have set aside your personal collection of scripts and plugins so you can just clean and start over? Uninstall even? hopefully you don't have tons of plugins and scripts like some seems to have, shouldn't be a problem if they are organized anyway.
Scripts and plugins are usually nothing to 'install, just drag & copy anyway.
So yes try, if you can yes, fingers crossed.
