Sure thing. open up a console window, I think you need to be root to do this as well, and type in "chkconfig firestarter on" without the quotes. That'll tell the firestarter service to turn on at boot. If you restart you're machine, you should see it start up when it starts up everything. Or you could just type in the command and leave it.
Hope that helps you out! Also, if you type in "chkconfig --list" without the quotes again, it'll list all of your services that you can turn on and off at will. You can also do the command "service firestarter on" without the quotes, but that just turns it on for as long as you have your machine turned on and it goes back to off when you reboot. If you have any problems or questions, feel free to ask!