When it comes to server operating systems, Linux is typically the default option. Still, some services offer a choice of Linux or Windows hosting. If you have specific server-side applications that require Windows, such as SQL Server or a custom application written in .NET, then you need to make sure your web host has Windows hosting. But don't let the idea of a Linux host intimidate you. Nowadays, most web hosts offer a graphical interface or a control panel to simplify server administration and website management. Instead of typing at the command line, you'll click easily identifiable icons.
Along with figuring out the overall category of your site, you should think about what (if any) exceptions there are to that. A lot of people set up a simple blog, and then realize they also want to sell just a few products. If you’re going to sell something on the website (even just a few things), you’ll need some kind of e-commerce software that will make that happen.