i didn't realise i had been logged out so my post updated with the next question didn't appear, or i dont think so, anyway.

i wanted to thank the guys who advised me on the file manager. that's working now, as far as i can tell. i haven't rooted the OUYA yet, as it seems not worth it, if it has to be redone after every update. i'll be guided by you experts on that.
my next question is, how to i change the size of the screen? atm, if i am in a settings screen for example, or when looking at the file explorer window, it's too big, so i need to bring all four edges in a bit. where and how to change that please?