No Microsoft will not call you to help clean your computer. What happens is you let the so called Microsoft technician take remote control of your computer and they proceed to install a back door Trojan that they have instructed your anti virus program to ignore. Now every time you open a browser on your computer the bad guy can see every keystroke that you do.
This means when you shop or pay bills the criminal will be able to see your credit card information. Your identity is at risk also depending on what kind of information you type. When you get a call saying its Microsoft calling to help you out just hang up and help yourself out.