ravmon.sys issues? (RAV antivirus)

Ive recently been looking for an antivirus for a friend. But because my friend is not very computer savy and resources are a concern I decided to look into RAV (despite the whole MS thing).

I put it onto a test machine and loaded it up on 2000pro with SP4 and latest patches. I also did some tightening of the OS and installed some other programs. But whenever I logged onto the internet (via dial up) I would get a BSOD . The stop code would also point to ravmon.sys. So Im like ok, probably just a software conflict or maybe something with SP4 and the latest patches. So I formatted the hard drive to start again. This time I installed everything one by one and logged into the internet every so often to see if I could pinpoint the problem. Had no problems so I updated RAV with the latest updates and noticed that it downloaded another ravmon.sys. So Im thinking great, maybe they updated it and corrected the problem. Right after I did my tightening of the OS, the BSOD appeared once again as soon as I logged onto the internet. So I decided to backtrack and remove each configuration one at a time to try to pinpoint which one it was. I was about to give up when miraculously I was able to log onto the internet without the BSOD. The problem seems to be with this registry configuration to stop port 445 from listening. http://www.uksecurityonline.com/husdg/windows2000/close445.htm .

If someone could confirm this I would greatly appreciate it.