best free anti virus available???

What is the best antivirus available that is free to download?
Hello,

FOR AntiVirus:

1) Antivir PersonalEditionClassic
-Free anti-virus software for Windows.
-Detects and removes more than 50,000 viruses. Free support.
2) avast! 4 Home Edition
-Anti-virus program for Windows.
-The home edition is freeware for noncommercial user.

It
is strongly recommended that you run only one antivirus program at a
time. Having more than one antivirus program active in memory uses
additional resources and can result in program conflicts and false virus
alerts.

FOR Antispyware:

SuperAntiSpyware - Awesome for on demend scanning, is updated everyday, good detection rate.
http://www.superantispyware.com/

Malware bytes anti-malware - Same reason.
http://www.malwarebytes.org/mbam.php
How is AVG Free Edition? http://free.avg.com/