Computer hangs periodically
I have an HP PC with Windows 7 Home Premium and an AMD Phenom(tm) II X4 840T Processor 2.90 GHz processor with 6 GB of memory that started to hang periodically for 4 or 5 minutes once or twice a day. It doesn't appear to happen at any particular time or with any particular application.
Once it it's finished doing whatever it's doing, it works fine for another extended period of time.
When I look at Windows Task Manager, nothing is using a significant % of the CPUs.
I've done a memory check. I've also messed with Resource Monitor and looked at "Analyze Wait Chain" and Event Monitor and nothing obvious shows up.
I've done a number of virus checks with AVAST and a complete boot scan with nothing too much found and no improvement seen.
I started to mess with ARO2012 and it found 2000+ issues, but thought better of letting it fix anything.
Sooooo, my question is where to start to actually fix this?
I could try a trial and error removal of programs from the startup menu, but that seems pretty random.
Is there a program that might actually "point at" the cause of this hang?
Is there a registry cleaner I should actually use?