The following are the advantages of using Linux based web server compared to Windows based web server:
1.Stable:

Linux/Unix operating systems has traditionally been believed to be very stable and robust. A web site housed on a Linux operating system will have very high up-time (of the order of 99.9%). Of course, other factors such as power supply, network admin skills, and network load etc. also matter when it comes to maintaining the system uptime.

The Linux OS comes free of cost (or at very insignificant cost, usually cost of distribution). Also, it has full fledged server, and desk top applications that comes free along with the OS. These server applications (such as FTP, Web Server, DNS Server, File Server etc.) being free, are also very stable.

When it comes to web hosting, it is easy to host on Linux web servers. The process of uploading and hosting is almost same for both Linux and Windows web servers. If you want to use a Windows based tool such as Front Page for uploading a web site on to a Linux based web server, make sure that the Front Page extensions are enabled. This is only required if you are uploading using HTTP feature (http://www.yourwebsite.com) of Front Page. Front Page also makes it possible to upload a web site using FTP. You need to select ftp://www.yourwebsite.com for up loading using front page FTP option. Note that if you select "Front Page Extensions" during web site design, you must enable Front Page extensions on a Linux web server also. These days, all Linux web servers are coming with installable Front Page extensions, and this should pose no problem for hosting on a Linux platform.

when using Linux web server.  Commonly, the following extensions are supported:.cgi, .html, .htm, .pl, .php, .shtml, .asp (requires additional plug-in), .xml, and others.Basically it means that you can host web sites that use different types of server side scripts including .cgi, .pl, .php, and .asp (with plug-in).

A web site designed to be hosted on a Linux based web server can be hosted on a Windows web server easily, where as the reverse is not always true. This provides flexibility in changing hosts as required.

Linux/Unix based web hosting is most widely used compared to Windows based web hosting, hence greater choice in choosing a web host.

A web site is dynamic. Usually, a web site starts with a few pages of html and grows over a period of time to suit the customers requirements. It is preferable to design a web site keeping this requirements in mind. A web site designed for compatibility with a Linux/Unix based web server meets the scalability requirement easily without making any site wide design changes.

If you are using any specialized applications or VB for development of your web site, it is preferable to host with a Windows based web server.