System hanging, Avast errors

Hello, I have been having an issue for a couple of months where my computer will freeze and/or react slowly along with other symptoms, such as the wireless adapter not functioning properly until a full reboot. I’ve spent a lot of time ruling out hardware failure and viruses and malware. I’m starting to suspect Avast may be partly to blame. In the event viewer (which I know can have all kinds of harmless errors), each time this happens I get errors from vboxasw support driver service, “failed to start due to error, system could not find the path specified”. Also things about 15 user registry files from avastsvc.exe, followed shortly by processor errors. Is this a dead end or is Avast really causing some issues for me? Thanks!
By the way, this is Windows 7 Home premium 64-bit running via Bootcamp with Avast Free.

What exact version of avast ?
Already performed a repair of avast ? If not, do so and check if the problem is solved.
If not, perform a clean installation of the latest avast version and check again.