My wife has been having all kinds of problems with her PC and she asked me to take a look at it.  She has become so frustrated that she is ready to buy a new computer.  Since that is not really in our budget Isat down to see what I could do for her.  I soon discovered that the PC was getting many common registry errors.  I found a program that would scan the entire system and make recommendations about files that should be deleted.  I think I hit the nail on the head.  The program is still running and has detected over 2000 errors so far.