There have been many flame wars, there have been different studies made regarding the security of each operating system mentioned in the title. The studies are sometimes said to be biased because it depends on what organization or company has funded the studies. At the end of the day, however, we must realize that no matter what operating system we use on our computers, we should be responsible enough to download security patches and the like.
Sometimes articles and threads on forums and blogs end up in fanaticism. Some of the points raised when it comes to vulnerability and operating systems would be:
The popularity of the operating system
Take for example Windows. It is probably the most popular operating system and some say that that is one of the main reasons why it is most attacked by hackers and creators of malware. They say that there is no point in attacking an operating system that is not used by many. The logic, they say, is that if you are going to do something, make sure it will be something big. (This is why there are people who seem to insist on getting a Mac — more stable and secure that way, as they say.)
Linux, BSD are operating systems that you can’t even run right away/properly/(insert phrase here)…
It sounds so petty, doesn’t it? But there are those who argue with Linux and BSD users that the difficulty with their operating system is that it is not easy to run it. Would an average computer users be able to use it and run it without much fiddling around? Truth be told, it looks like it is possible. But that depends on which Linux distribution you would run. In any case, the argument is more along the lines of “If you can’t even have the OS running properly, who would bother attacking it?”
Everyone must learn how to set up security measures. Be it setting up a firewall, being careful about which sites to check out, downloading patches — each of us will have different needs and we will have different experiences.