Windows 7: Windows freezes on me

I don't know about you guys, but I have been having weird problems with windows 7.

1). When I open network and sharing center and I goto change adapter settings/enable or disable.

I do this to make windows be completely offline, when I am working with sensitive documents for my dad's business. However once I choose to disable the network adapter, windows will completely lock the whole system up within 30-60 seconds from the time I disable.



What I want to know is how do I stop the lockup?

I think there are a few possibilities for this one, so let's try to narrow it down:

1) Do you have the latest drivers for your network adapter?
2) Do you have an antivirus program installed, and if so, which one?
3) Does Windows just, BAM, freeze completely, or does the cursor remain active, but anything you click on just locks up?

1). Yes, I am using Nvidia 15.53 WHQL Windows 7 x64 motherboard drivers
2). Avira and NOD32, but it even does it with windows firewall and NOD32
WF + NOD32 was my starting config, I just switch to comodo and Avira last night.
3). It completely freezes the mouse and everything. The whole system is completely locked up.

The att modem that I use for my 6.0mbps extreme dsl is 2wire.

For trouble shooting purposes, download Microsoft Security Essentials. Uninstall Avira using this tool > Info > Tool. Uninstall Comodo. Go to their website and use their uninstall tool. Install MSE and make sure Windows Firewall is enabled. This will eliminate the possibility that Avira or Comodo are causing the problem.

Just to be sure, and in light of CarlTR6's suggestion, were you having this problem prior to installing Comodo and Avira?

Since you know how to cause the crash, try playing some audio in the background, and then repeat the steps that trigger the freeze. See how the audio playback changes; does it just stop completely, start rapidly skipping (like a buzzing sound), or continue playing normally?

In my experience, if both the entire system and cursor freeze and the audio starts rapidly skipping, all at the same time, it generally indicates a hardware problem of some kind.