Baking soda and a little bit of water stir till it turn's into like a paste then use like an eye glass cleaning cloth and put a little bit of the paste on the cloth and gently rub it on in little circles let it sit till it drys then use a very damp peace of soft cloth to wipe it off dabbe it dry with paper towel. If that don't work use lemon juice.
if you have a nother computer and have internet you can google Hirens Boot disk and download a coppy of his password recovery boot disk. you download the program to another comp. then burn it to a blank dvd disk then use it to boot up your other comp.