Linux is known as an "open source" operating system. i.e. there is no licensing fees to pay. Therefore, compared to Windows, Linux is very cheap. Starting with Windows XP, Microsoft has begun enforcing software activation. This means that a single copy of Windows can only be installed on one computer. With Linux, once a copy, has been purchased one is free to install it as many times as one wishes on any number of computers.
Reliability
Linux is reputed to be very stable and reliable. This means that a Linux server is much less likely to crash than a Windows server. Subsequently, a Linux server will mean more 'up time' for your website. (Watts Humphrey, pp. 77)
Experience
Linux has many more years of experience than Windows in hosting.
Speed
There is no real difference in speed between Linux and Windows, but Linux is slightly faster in processing basic web pages.
Functionality
Windows support ASP (Active Server Pages), a Microsoft programming/scripting language, which allows you to build dynamically database-driven web pages by connecting to a Microsoft database such as SQL Server or Access. Linux does not support ASP nor Microsoft databases, but uses MySQL database instead.
All Linux accounts come free with Frontpage extensions, which allow you to upload your Frontpage website to your web space on a Linux server. Watts Humphrey, pp. 81)
Scripts
There are many CGI programs available on the Internet. The majority of these are Perl scripts and have been developed on Linux / Unix web servers. So they tend to install more smoothly and operate more reliably on a Linux server. Moreover, many Perl scripts are downloadable from the Internet free of charge.
To summarise, most users find that Linux hosting is easier to use, more reliable, provides free, open source software and is much cheaper than Windows hosting. So unless you particularly need to use ...