fedora 10 firewall: to check or not to check

[baerb8]

i am not sure if this is the correct place to post this question or if i should have gone into networking.
anyway, it is a typical newbie query: in the firewall settings does a checked box mean block this port or open this port? i had both Samba and Samba Client checked then unchecked them both again.
i want to network my xp and my leopard machines with fedora 10 and am trying to use Samba. so far no luck either way i had the firewall set.
i know i have on top of that other networking issues but those i know not to post here.

please, can someone enlighten me,

[Evil_Bert]

Checked means open.