root GUI login in fedora was REMOVED way WAY back in fedora 10 ( fedora 8 and 9 gave a "--WARNING-- do not login as root")
in fedora 10 to "the end of time"
root gui login IS not ONLY disabled BY fedora
BUT BY GNOME ALSO
( yes there are ways around it
but if you do not already know HOW to do that then you should NOT be doing that
ALSO stay CURRENT fedora 15 hit it's END OF LIFE last month
Install the Current and supported version "Fedora 17"
i can log in as root from terminal by use su command
you NEED to use " su -" ( see the " -" in there )
fedora separates things that a normal user can do and what ONLY ROOT SHOULD be able to do