If it's your business computer and you want to really be safe, get a real hardware firewall such as a Sonicwall, Cisco PIX ($$$), or Netscreen (PIA to adminster). Expect to pay at least $500 for the privilege, and a yearly fee for support and updates. Then get an antivirus software solution of your choice (NAV is probably liveable, but Symantec Anti-virus is much less flashy, and other programs may do better). I'm currently recommending Ad-Aware SE as an anti-installed spyware program. As far as preventing spyware, I don't have any particular software for that in my portfolio at the moment, but I imagine there's some good ones. Also, keep running Windows Update.
