what is best anti virus for PC..

There are a lot of good free antivirus you could download these days, my personal favorites are Avast, Microsoft essentials and Kapersky. I am now currently using Avast because it has become one of the most recommended antivirus in the world. It is free and it is easy to use. My anti-spyware program I use is Malwarebytes. I am not sure though if it's free, I just got it when I have my laptop already. It is really a good one. It could detect your computer from harm and it could stop the pages that you are about to visit that has spyware or malware in it.