seriously, i dont think there is such a thing as the best antivirus. coz antivirus developer enhance their product frequently, the antivirus that you should choose will be the one that suites your taste the most.

but many uses,
bitdefender, antivir, kaspersky,avast and a few more, search the forum for antivirus, if not mistaken, there is one thread which allow the lowyat user to vote for their antivirus.

i personally prefer avast...