This post was published 5 years 7 months 22 days ago. Therefore, it may well be out of date. Do not reply on the contents of this post being accurate. 
If you fancy breaking away from proprietary OS software (e.g. Windows XP or others) I recommend using Fedora Linux.
Fedora Core is a free operating system that offers the best combination of stable and cutting-edge software that exists in the free software world.
The latest version, Fedora Core 5, is a great looking, fully featured and easy-to-install operating system. Based on RedHat Linux and with its own development community it’s one of the most popular Linux distros around.
Naturally it’s also open source and is freely available to download (or, even better, pick up a copy included with one of the many Linux magazines available). The install disc includes everything you need to set up a server or desktop version or both.
I’ve installed it on a spare machine with an AMD Athlon 2200 XP and 768MB RAM (a far higher spec than is required). The install picked up all of the onboard devices and PCI cards (NIC, VGA, sound, etc.). It really was a breeze to install and is a really great looking OS.
If you’ve got an old unused PC lying around why not give it a whirl. I think you’ll be pleasantly surprised.