Linux vs Windows Web Hosting
Linux
Linux is a good choice if you plan to use PHP, Perl, Python or MySQL on your website.
Applications you use on your website with Linux are more likely to be open source (which mean they are free to use).
One type of application is a content management system (like WordPress).
Linux is also considered by many to be more stable than Windows and is the best choice for the web.
Windows
Windows is a good choice if you plan to use Windows applications on your website.
ASP (Active Server Pages) is used on Windows and is the alternative to PHP. MS SQL is the database that Windows uses.
Applications available for Windows are more likely to be based on purchasing a license.