I'm searching the config file that says which extensions are active beacause i want take it in /etc/skel directory. also i'm searching too the file of theme configuration (that says which theme is active)
You need to use skel for this:
I'm not sure if this will help in all aspects of your question but have you tried the
It will definitely show you which theme is active plus it has the following features.
There is also an indepth article that I have linked to below that explains customizing the GNOME Shell. It explains how the GConf CORBA-based configuration system is no longer used and has been replaced by GSettings which it goes on to explain in detail.