avira

Emsisoft Anti-Malware 8.1

30 day trial/freeware - Switches to freeware mode on 30 day trial expiry

https://www.emsisoft.com/en/software/download/


Malwarebytes Anti-Malware 1.33

Comodo Internet Security

Comodo Internet Security

Complete protection: AV, firewall, anti-spam...

avg gives a lot of false positive readings, has become unreliable nowadays.
ms security essentials actually has come a long way, was rated in the top 10 last year i think for free services (if u have a valid windows license)

using bidefender total security

free try Microsoft Security Essentials

avast

Avast

i think avast would be your best option...or you could torrent a kaspersky

AVG the best, I'm using AVG

Bitdefender Antivirus Free Edition (2014)