Windows Operating System not being monitored

Question

I have installed some of the management packs (advanced workflow module events, event log provider events, performance monitor porvider events, registry provider events, script and powershell provider events, service monitoring events, vmi provider events) and
there are no overrides.  I still cannot get the windows operating system to get monitored.  I have restarted the server and still none of the windows operating systems are being monitored.  Is there a certian management pack that i need to install
for the monitoring Windows Operating Systems.  

Answer 1

dktoa is correct, just because you have the Agents installed does not mean that anything is actually being monitored. In fact, all that will be monitored is the Agent itself being able to communicate with the Management Server. 
However, I would suggest to ensure that all of your Agents are reporting back as Healthy (aka green), before you import any Management Packs. That way any issues that may occur can be directly linked (and thus troubleshooted) to the MP.
Additionally, you have not mentioned what Windows OS you are trying to monitor. More than likely it is a Server OS; in which DKTOA has provided the link for the Windows Server Operating System Management Pack. 
However, if in case it is a client-based Windows OS (i.e. XP, Vista, 7) than that Management Pack can be found here: http://www.microsoft.com/en-us/download/details.aspx?id=15700.
You should note, that there currently is no Management Pack for Windows 8; though it is due out soon.