Unfortunately, The Main desktop edition of Fedora 17 is GNOME. GNOME won't let you customize your computer's settings and let you be free to control your computer. Try other spins of Fedora, or if you really wanna stick with GNOME, you might wanna install the package "xscreensaver" and run it from command-line. And, try to config settings from there.
Hope it works. but, you should send a message to gnome by not using gnome.
Secondly, the system logs off because of the unstable of GNOME 3 acting with X Desktop.
Thirdly, You can't open true type font file, you mean, your browser or the word processor does not detect it?
Are you sure you've installed it? If not, create a directory ".fonts" on your home folder and paste the true type fonts you need in there.
If yes, blame gnome 3 for no freedom in desktop.
Last edited by suttiwit; 10-01-2012 at 10:36 AM.