The answer to that question is an opinion. There is nothing "technical" that makes one better then the other. Unix (on which Linux is based) was doing networking backs in the 1960's before Windows even existed, so it became the backbone of the early Internet. Windows did not add network ability or a brower until Windows 98.
Because it was there first, Unix/Linux has remained the OS of choice for many web host. However Windows has caught up and offers everything that Linux does in the way of Internet hosting support.
Because Linux is a free program, and most of the software that runs on it is also free, it is often cheaper to host a web server using Linux than Windows. You do not have to buy any of the software. You simply download it.
But you have a larger learning curve. You have to learn Linux, which is very different from Windows. While Linux does have user interfaces, most things are done through a command line. You have to know the often cryptic commands needed to do anything in Linux. I do not know that Linux is any harder than Windows, it is just different. You have to learn it.
Finally, a lot of the newer technology, such as .NET, is Windows only. Also the most common database used on the Internet is MySQL, which again is Windows only based. Over the next few years expect to see Windows pull ahead of Linux and eventually leave it behind in web hosting as it has in everything else. While Linux is an excellent program, it does not have the resources and support of the Microsoft giant behind it.
Use whichever you are comfortable with. Neither is "better" than the other. They are just "different". They each have strong points and weak points. The "right" one will be the one that works for you.