No single package can be completely trustworthy as they can only be as good as their own particular set of definitions but as far as these things go Kaspersky has the best reputation, but it's expensive. Being an absolute miser I only use free apps and currently run ZoneAlarm for my firewall, although it hasn't actually had a single incident since I started using a wireless router with it's own, built-in, firewall. I run Avast as my main anti-virus, although AVGfree is good as well but it needs extra work to run with the NET apps I like to use. I also run regular (at least once a week) scans with AdAware, SpybotS&D and Malwarebytes Anti-malware. These free apps can be scheduled to run on a regular basis but I find it annoying to be in the middle of doing something only to find everything slows to a crawl when a scan runs (my laptop is over 7 years old, I really ought to re-install Windows and my ISP is renowned for strangling bandwidth, but that's the curse of the miser) so I make sure I find time to run the scans when I'm away from the 'puter. The only serious infection ocurred when I clicked on a link in what looked like a perfectly innocent email, and that took a week to eradicate with the help of the techie at Karls Forums who is very good at dealing with these things.