Well you can doubt that, that is your choice, but do you have any facts on your side, that are stronger than the fact that Windows is the OS most of the people around the world use? I can answer that for you - No! Because there are many factors that make an OS good, not just stability or open-source capabilities, for example. In the case of Windows this factor is ease-of-use, and judging by the numbers, most of the consumers consider this factor to be important!
By the way, you might get ideas that people don't choose Windows, they are forced to use it, because it comes pre-installed on their PC's, though I can say that that doesn't matter, because they can install a free Linux version on it, nevertheless, if they choose to do it!