So i am having some trouble trying to play skyrim in full screen through HDMI see this post

http://www.gamesas.com/topic/1398066-hdmi-overscan-problem/

Anyway i am going to try to force it in the ini, am i right in thinking it's the one in "my documents games skyrim skyrimPrefs" and these are the settings to force full screen

bFull Screen=1
iSize H=1080
iSize w=1920

You are right in thinking that the only INI you want to mess with is in the My Documents section. Even then, make a back up first.

However, the screen res is in the Prefs file, not the INI file

Thanks i don't have a prefs file only a skyrimPrefs i take it thats the same thing ?

Yes, I leave off the Skyrim part. Skyrim Prefs is the one you want to change.

For the record, the INI file is not called INI, but just Skyrim, but people still refer to it as the INI.