? from UberNewbie Where is Site Admin?

[leetaylor]

Hey folks Lee Taylor here. I am not familiar with any of this, however I have got XAMPP up & running on my Dual G4 running Mac OS X 10.4.11 Now trying to install Gallery 2 (http://gallery.menalto.com)
which requires FFmpeg module & FFmpeg lib. The instructions are to go to Site Admin > FFmpeg > (in the Graphics Toolkits category) & activate the option...

I am not sure how to get to Site Admin & not sure of where the Graphics Toolkit(s) are.
Anybody got time to drop me a simple explanation of how to do this?
I would appreciate it.
Thank you
Lee