Internet connection dropping when inactive

Hello forum users

Comodo Firewall version 3.5.57173.439
XP Home Edition version 2002 SP3
Avira AntiVir PE Premium
PARVAK Panda Anti-Root kit
Advanced System Care

Problem; Internet connection drops out anywhere between 3 sec. to 3 mins when im inactive.

Reason After reading thisand failing the NETbios security test section i desided to disable NETbios within the 1394 connection, Local Area Connection and Virtual Private Network. Then reran the test and found ports 137,138,139 were open. I changed the stealth ports wizard in comodo firewall from ‘block all incoming connection stealth my port to everyone’ to ‘Define a new trusted network stealth my ports to everyone else’. Ran the test again and passed the stealth test. Not sure why those two setting are different and cause my ports to be closed.

Solution I Enabled NETbios ran the test again and passed all sections, how and why i cant figure out. But all this has left me the problem of the connection dropping out.

Can anyone enlighten me on what has happened and possibly advise a solution or even run though how i should have my firewall configured.

Thanks for your time

Regards, Matt