[K12OSN] Change configs?

[Brad Bendily]

Ok guys. I have LTS up and running and my client logs in and runs the desktop.
I get the full Gnome desktop. What I would like to have instead is
just X running
and load Firefox. I have done this on other distro's and it was fairly
easy to do.
However, i'm not sure where I should start looking to do this in LTS.
Can someone
point me in the right direction? How would I switch to a KDE desktop? Where are
the configs for each desktop stored? Where are the file for each desktop?

Thanks
Brad B