i bought a xbox on ebay and its "modded" what can i do with it and.where do i start?

what can i do with it?
where do i start?
how do i find out the info i need know?
i do know from reading other threads that it is a "dual boot" ? i know this because it can load up two diffrent ways
the seller of the xbox did give me some info to get started, but he is gone now, i made him mad on an unrelated issue.
so i have imgburn and from reading other threads i've downloaded a few other things, but not really sure i have the info i need about the xbox itself, or what it is running (?) my main objective is to be able to cop y my games because i have small children that think dvds and such are industructable,
also it seems it has a media dashboard (?) anyway has menus for music, movies and such,
bottom line i need all the info a xbox dummy could use once i know what i have i can go back to learning the how to of everything, thanks so much.