Microsoft Security Essentials has a quite a good reputation among other users whose opinions I trust, though I can't say I've used it myself. I have used Avast Internet Security for several years now and am quite pleased with it, though the new UI they came out with isn't my favorite. I chose Avast primarily due to its low impact on system performance, but also because it has a solid detection rate and mitigation ability for unknown threats.
As an auxiliary to your antivirus I highly recommend Malwarebytes AntiMalware
. My understanding from persons who would know, which is corroborated by personal experience, is that MBAM focuses on detecting and removing malware which other scanners generally miss. Both Avast
and MBAM offer free versions, but their paid versions have extra features which I think make them worth the price of a license. For example Avast Internet Security and Avast Professional both can optionally sandbox selected applications (you can do this without Avast on 32 bit editions of Windows 2000-XP by using Sandboxie
) and the paid version of MBAM offers real-time protection as opposed to the free version's on-demand-only protection.
If you are running Windows Vista or Windows 7 then Microsoft's Windows Defender application is already installed and should be running. Windows Defender is available for XP as a download from Microsoft
, but is not available for versions of Windows prior to XP.
So, my recommendation mirrors my own setup: Avast (Free, Pro, or Internet Security) as primary defense with MBAM and Windows Defender bringing up the rear. These tools, coupled with common sense security practices on your part should render your PC all but impregnable to the vast majority of threats.
Edited by Andrew, 06 December 2011 - 07:02 PM.