Bdis 2010 Firewall Prob

My PC has two net cards. First is connected directly to cable modem, and second connects my PC (host) with my wife's PC (guest) via cross-over cable.


Both PC's are on WinXP SP2 32bit.


I just discovered something that seems to me quite odd.


I set Protection Level to Report to have full control on what's trying to connect to internet and set rules manually.


This setting is absolutely a must for my PC configuration.


Now the thing is that whenever I Enable Internet Connection Sharing in Advanced Settings Window, the rules don't apply at all.


I mean for example I can deny access for my browser or email client, but still both programs connect to internet they simply ignore the settings.


If I Disable Internet Connection Sharing, the rules work but there's no connection to internet from the second PC (guest). My PC is host.


Trying lots of possible settings I've found only one solution to have both, rules working on my host PC and internet access from my wife's guest PC -- and the setting is Stealth Mode OFF on a my PC network card with direct access to internet, and Internet Connection Sharing disabled.


Then the rules work and my wife has internet access from her PC, even when ICS is disabled.


This might work fine but isn't it unsafe to leave StealthMode OFF all the time?


Or maybe there's another solution?