FYI. Follow up on original thread: http://www.sevenforums.com/crashes-d...esponding.html
I upgraded my system (motherboard, CPU and memory) and the problem still persisted. I found threads on other forums which lead me to the solution.
I originally had Windows 7 loaded on a 500 GB Western Digital Caviar Green
drive. Found several reports that Green drives were problematic, especially as system drives. I purchased a new 500 GB WD Caviar Black
drive and used the Acronis True Image software available on WD's website to clone the Green drive onto the Black drive. Removed the Green drive, using the cloned Black drive as the new system drive.
After two days of pounding the system (simultaneously playing videos, recording TV, surfing, running virus scans, Windows updates, software installs, etc.), have not seen a single instance of Windows Not Responding. Previously, the system was freezing every 5-10 minutes.
Using Resource Monitor, I've observed Disk Queue Length of up to 10 during heavy disk activity. The Green drive would freeze the system at queue length as low as 1. Response times would rapidly rises to thousands of milliseconds. The Black drive has never chocked, even at higher queue length, and the response time remained under 10 ms.
Hope this information helps others with similar hardware!