Hi, if the CMS written by PHP, it can running on both Linux and windows. if by ASP.net, it only can running on windows .
You have to keep in mind that PHP applications love Apache environment, and there may be issues with running it on a Windows (IIS) server.. So I'd stick to Linux if I were to go for a PHP script.
Just to clarify what CliveRay said: yep, PHP + IIS is a little more finicky. However, I wouldn't say 'stick to Linux'... though I would say 'stick to Apache' (which, obviously, runs nicely under Windows, too).
True, I have Apache installed on my localhost which is a Windows OS, no issues with it. On live hosts, however, you will rarely find a Windows + Apache server option, it will most likely be a Linux server with Apache running on it. Generally, windows servers are not the best choice if your scripts are built on PHP.. Windows servers are more costly to administer and maintain, while Linux servers are generally known to be more secure, and cheaper.
Many Windows servers allow you to run both ASP and PHP scripts, while some *NIX server are ASP apache enable, a cgi module to run basic ASP routines. The clue is inside the configuration file since those PHP scripts designed for Linux servers require a modification in the absolute path to run on Windows with no major hassle, unless they need specific linux side scripting. Good place to find and try CMS's: http://opensourcecms.com Code (markup): _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Green Rep is always welcome