billythekiddo - 11:25 pm on Mar 3, 2005 (gmt 0)
Format all computers and install windows again on all computers. Buy a modem / Router with firewall support (Draytek 2600 for example), it is much better then a software firewall. To prevent viruses on your computer use McAfee and not Norton.
Make a mirror drive of every computer. If you do not trust a certain computer just format the drive and get the original configuration back using the mirror you made earlier.