I came across this story about Windows vs. Linux Servers on the IT World Website. The supposed expert states things like "Windows access control "blows Linux out of the water," he claims. "In a Windows box, you can set access-control mechanisms without a software add-on." " Since I setup access control on Linux servers on a regular basis. I have never needed a software add-on to do it. Several of the companies I have worked for have used tools that manage all of their servers in a unified and automated manner. These tools however were used for all of the systems in their environment be they Unix, Linux, Windows and even the Mainframe.
The "Expert" also seemed to think it was harder to manage a Linux Server over a Windows Sever. This is strictly a matter of what you are used to. While there were times in my past where I did Administer Windows Servers. Going back now and trying to do things is difficult because of how much has changed. Learning and becoming an expert in any operating system takes time and requires work.
Companies need to evaluate the Linux vs. Windows choice based on what they are trying to do. Everyone needs to not make this decision on a case by case basis. There are no hard fast rules and staffing and cost will always be the biggest things to determine it.