I have used Linux in both environments (Desktop, and Server). Linux is a very great platform for many reasons with reliability being one of top features I use it for.
There are a couple of distributions that I alternate in use, or have more than one machine running either as the host or using a program to run one ‘inside’ of another, such as VirtualBox.
Debian is one of my favorites. I have only used it for servers so far, but I must say it does a great job. They have several different downloads you can choose from. The one I use the most would be the netinst (net install) ISO file. It contains only the minimum needed to get Debian up and running, and provides you with a method to download and install packages, so you are only putting on there what you want, and don’t have to spend time removing applications that you never intended to have on there.
Arch Linux was both my server and desktop operating system for awhile at one time. I originally downloaded and tried it at the request of a friend, but after using it I liked it more and more. It’s pretty quick to install, and once you get the hang of it, fairly easy to use and maintain.
Currently I am using Windows as my desktop operating system, but when I made the change I didn’t have another machine good enough to run Windows around. Unlike then, I have a laptop with Vista preloaded on it. When I get around to it I will be putting XP on my laptop, and Debian back on my desktop, which is currently running XP.
A friend of mine posted something similar to this titled Why I use Linux. I thought it was a great idea to tell others about my reasons for liking and using Linux too.