I had never used Linux and decided to try out Ubuntu, mainly as a hobby. So I installed Ubuntu 10.04 Server shortly after it was released and in all honesty, it really hasn't been all that difficult. You can find help for almost any problem that you run into by using Google. If you aren't a big fan of the command line prompt, you can install Webmin which can be used for pretty much everything that is related to administering and running the server.
I started off with a basic LAMP installation so that I could run a website and since then, have added personal e-mail, media streaming, Internet radio station, webcam monitoring, Teamspeak and Ventrilo server.