Hi

Closing listening ports is a good line of defense. If you have a stand-alone desktop
with internet connection, I do not really see why not to close all of them (Are there
drawbacks? I haven't experienced any yet.)

For example, to close Port 445 completely (not tested on SP2), a little registry tweak
is needed (make a note of what you change or export the key first.)
Code:
HKLM\System\CurrentControlSet\Services\NetBT\Parameters
set TransportBindName from "\Device\" to a blank value. Reboot.

For additional information, see a tutorial[1].

Cheers.

[1] http://www.antionline.com/showthread...hreadid=264811