Computer keeps shutting down. Worse CC

I have no clue at all what is wrong.
System keeps turning off (I mean OS I guess is what keeps shutting down as opposed to the power actually going off).
Now it seems far worse after running C Cleaner. I usually Wise Registry Cleaner but my system has been almost at the edge of lock up a lot lately.
I run the following at least two times a week:
AVG
AdAware
Iobit Defrag and Optimize
McAfee
Wise Registry Cleaner
eSquared

and a couple more.

Any ideas?

 

Excellent advice. I don't know why I didn't think of that backup myself.

As for the phantom SP3 error problem in December, it suddenly quit coming up. Not sure how that happened, but am really glad it finally just stopped happening.