Recently, a friend of one of my son's visited some sites, one of which which downloaded a worm while they were on our family computer. After installing Norton internet security and Ad Aware from
www.lavasoft.de and also making sure the Windows XP firewall was optimised, I now get no pop-ups, attacks or unauthorised access. Ad aware also removed 87 unauthorised programs.
And my son is banned from going on the computer with his friends!