but where is the equivalent for windoze, the very common and very vulnerable opsys?

IMHO, the best place for windoze folks to start is here http://security.kolla.de/ This tool detects and removes a whole pile of nasty intrusive software that virus scanners do not pick up. And Spybot S+D also has an immunize function that can block future intrusions. Of course, they could also buy and install some commercial windoze firewall software but the cost of this is a barrier for a lot of folks unless they have seen it in action on a friend's machine. Beyond this, http://www.apple.com is a good place to find solutions to this problem. --Michael Dillon