Basically it really depends on you.
Use window if you have knowledge.
Use linux if you have knowledge.
Use what you like best.
Each OS isn't better than the "other" each has cons and each has pros.
Window best game panel would be TCadmin
Linux has panels like swiftpanel, mintpanel, gamecp, and others.
However I think Linux best one is swiftpanel.
But, TCadmin is the best panel overall but only runs and works on Windows OS unless you can code it up for linux.
Also depending on what games you are looking to provide or host.
such as counter-strike or team fortress 2
window server 2008 with hpet + fps booster you can gain 1000fps 100ticks.
window server 2003 can only reach about 500-600 fps max.
linux you have to build and compile your own custom kernel to reach stable 1000fps.
Linux is the most stable of all 1000fps.
However, like I mention each has pros and cons.
Don't run in to the industry, until you do some research.