Actually the best operating system for security is Linux but it isn't easy to use which is why it isn't mainstream at the moment. However, on the plus side is that it is not a resource hog like Windows and it can easily be run on a low end pentium. Another benefit is that it is open source and hence free. When I have time I will be creating a Linux partition on my pc and I will test it out since it has been a few years since I have actually used it and that was in the workplace.