Here is a program that is well worth the money. I have use it for a year...it is called, Reimage. Google it and find out about it. Anyway I just renewed my subscription for for another year. The program scans your computer, deletes bad and broken files, deletes any viruses it finds and then here is the good part. It replaces all the bad files it deletes with good, brand new files from the microsoft storage.. it will tell you about your computer, how it's running, it will fix the registery etc etc etc...if you have a very bad problem and you can't seem to fix it with reimage, they will make an appointment with you and then do a remote session and fix everything...here is a link to read about it....
http://reimage.org/