We generally do not recommend adding rules to the firewall tab, unless you have a specific reason for doing so. There really aren't any best rules to add that will prevent attacks.
@Kraze^NFo> Juski has a very valid point
@Juski> Got my new signature, thanks!
@Kraze^NFo> Out of context!
@Juski> Doesn't matter!
@Juski> You said I had a valid point! You can't take it back now! It's out there!