Personal file sharing is for networking with nearby computers & equipment.

The most important thing about the osx firewall setting is you have the limewire/gnutella setting. The port numbers may change from time to time if you are using UPnP. So use the default should be fine afaik. If you port forwarded your modem/router then use same as those.

Personally I rarely use my osx firewall. Unless I'm browsing places I am suspicious of.

BTW sorry for the very late response.