Hello,
Anyone know some aplication that setup the firewall of linux, without the complexity of iptables rules?
More visual, more easy.

Check out a program called Firestarter. It's probably just what you ask; there are surely others, but that's a known one. It's a "graphical front-end for iptables", and though some newbies believe it's a firewall, it's just an interface run once, create rules, save them and that's it. Probably you can choose whether iptables itself or firestarter should load the rules at startup, but it's all the same -- the result doesn't change, since iptables still does the job.

So, try Firestarter. In my opinion it's a good idea to learn to use iptables too, it's not complex at all -- if you take a short firewall example script (can easily be found on the net, maybe even in iptables.org), you'll learn it quicker than you think. With scripting it opens you a whole new worlds, without the need of having X11 around.

...and, once you have Firestarter (or Guarddog if you use KDE) working; you can still look at the output of # iptables -L -n to see how the rules change as you alter them in the GUI interface.

I use Fedora 5 with the default Firewall (meaning the firewall had been configured during the installation, it´s not a manual configuration). Is Firestarter compatible with the Fedora´s default configuration´s tool?
I read that once you had been using this tool, you shouldn´t attempt any change manually, but always make any change by using the FC configuration´s tool. The problem is that this tool doesn´t allow much. Can I just use Firestarter without fearing any conflict? Will it save the rule under the same file or some place else?