kaspersky its simple and easy to use. i once had a very big virus on my laptop. i downloaded a trial and it removed it so fast so the next day i went to the shops and i even asked the worker he said it was better than Norton and other garbage
Many people use AVG, Avast and Kaspersky. But I think to deal with viruses and malware especially those stubborn ones, we had better get rid of them in manual way. That is because PC viruses can mutate all the time while antivirus requires time to update the database. But if we know computers, we can locate files dropped by threats to clean them as well as threats. I have always followed a professional blog named http://blog.doofix.com/, you could have a try as well once you encounter PC problems.