First let's start with a definition of an operating system, which is software platform on which a web server runs.

Red Hat Linux:

Linux is an excellent operating system that is well suited to meet your web hosting needs. It handles functions of mailing, and serving up Web sites and files especially well. Additionally, there are a huge amount of free applications available on Internet for Linux and it uses less hardware resources than Windows 2003. Whether you are a fairly experienced webmaster or new to web hosting, we recommend that you choose Red Hat Linux as your hosting platform.

Red Hat Linux is most widely used hosting platform in world.

Microsoft Windows 2003:

Before you start make sure this is something that you have knowledge to do and not just from reading books, but where you have worked on them. Running servers may sound easy, but it's far from easy, in fact, even people experienced with servers will have trouble with them from time to time. You will have to deal with security threats, downtime and fixing program errors.

Starting your own hosting services is going to be challenging and frustrating. One option to think about is reseller hosting plans. There are several good web hosting companies out there that offer reseller hosting, but at same time allowing you to get paid, but without you having to spend your time maintaining servers. You may want to start out this way to get a customer base going.

You can rent, lease or buy your servers, If you decide to buy servers, get them custom made to your exact needs, if you have money, if you can't try to get a server that best fits into your plans. You'll need a place to keep servers. You can find local building to do this or you could keep them at home. If you keep it at home, you'll need to make sure everything is just right for them.