Who trusts Microsoft like me ? and use the green icon on taskbar ms essentials . and a firewall app.
Trusting any antivirus by itself is just not wise anymore. It's a third-string defense at best. If you want a low-impact defense, start by maxing out your UAC settings and using a non-Admin user account (aka Standard User on 7 or Vista), install Microsoft's EMET and configure it
like this, disable AutoRun using the Fix-It from
this page, and enable Software Restriction Policy in disallowed-by-default mode
like this if your version of Windows supports SRP.
Also, uninstall any unnecessary software (Java most of all), get the most recent flavor of the stuff you need (e.g. Adobe Reader 10 versus 9, Flash Player 11 versus 10, etc), and check the rest with
Secunia's installable PSI utility. You don't have to have it run at startup, that can be turned off... just run periodic checkups to see if you need some security patches.
Lastly, use a web browser that takes advantage of WIndows Integrity Control and/or sandboxing, which last I checked limited the field to IE and Chrome.
To illustrate why not to trust your antivirus alone, and not to get too bogged down in AV-Comparatives and such... at work, I was setting up Win7 on a server, and I was all
Hey, I need the software for the APC Smart-UPS SC 620 uninterruptible power supply. So rather than wade through APC's site, I hit Google and googled the product's page at APC's site.
Then I went there, and was promptly attacked by a BlackHole exploit kit. At APC's site. A safe, normal business site. Being me, I captured the JavaScript file that was used to launch the exploit and submitted it to VirusTotal.
Detection rate: 1/43 (it just so happened that Microsoft's engine was the one that detected it, but that's just a roll of the dice). So much for relying on antivirus protection. Too little, too late, too seldom. If you want to be protected in time for it to actually help, see the list of steps I gave above, it's worth far more than AV in today's world. In my case, those steps saved the day for my server setup.
So going back to the original topic, yeah I trust MSE, but as a third-stringer in an overall defense-in-depth approach. The A-game is played by proactive mitigations as described above.