"I have contacted Sony and MS Tech. Support but they only recommend 'Full Recovery' which I am reluctant to do in case valuable data might be corrupted or lost"
Always create a backup of your data onto an external drive do not just keep it on your computer. Once you have backed up your data you can then do a full recovery.
Note: if you do not back up your data and your hard drive fails you will loose it.
I would suggest testing the HD as this can cause an intermittent blue screen.