The answer is none of them, if you were to use an Antivirus that included all of the AV engines together you would be lucky if 50% of malware on the web would be blocked. Let's face the facts an Antivirus is just a helper, you have to do the main job by controlling your actions when downloading files and using common sense.
1. Utilize UAC prompts (never approve anything unless you know it is safe)
2. Choose an AV that is light on your system, user-friendly, low false positives, has no compatibility issues and easy for you to understand.
3. Keep Windows and your software updated.
4. Never download files from suspicious unknown sources.
5. Never depend on any AV to fully protect you because they will not.
There is really no point in these kind of posts because members will just vote for their favorite software ignoring logical facts.
Thanks.