Hello!
I would like to point out a possible error I found.
I am using Windows 7 Home Premium and have Microsoft Security Essentials installed and enabled.
Security Essentials work as an antivirus.
Windows Defender, as far as I know, doesn't even exist anymore (at least it's not supported).
But what I got from Speccy is:
Operating System
MS Windows 7 Home Premium 32-bit
Installation Date: 09 November 2010, 19:40
Serial Number: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
Windows Security Center
Firewall Enabled
Antivirus Disabled
Windows Defender
Windows Defender Disabled
...which I believe is not true...
Hope this helps.