firestarter error and changing resolution
 

I have installed fedora core (server) on one of my pcs to use as a server but i am having a problem setting up the internet share. (internet through usb home network through ethernet d- link hub).

I have installed firestarter and set everything up as per their website but when i try to start firestarter i get the error message "failed to start firestarter" but if i ok the message i can change the settings etc but when i try to save them it comes up with the same error message i had a problem of the dhcp being greyed out but ran yum install firestarter which sorted it. i have a xp machine and another fedora desktop to network. when i set the network manually i get connection but no internet and if i use dhcp i get an error partial connection. i found another website shaftek.org/blog/archives/000182.html which showed you how to amend the files manually but i do not have access to the files. i get permission denied when i run /etc/dhcpd.conf.

I also have a monitor which runs at 1024*768 at a refresh rate of 60 but linux will not let me set the refresh rate before the resolution but then bombs out because of the refresh rate./etc/dhcpd.conf

I have not seen linux before last friday so i am still struggling to get to grips with even the basics so any ideas are welcome.