I have tested various Linux Distros including Xandros. Personally, I would suggest Arklinux(http://www.arklinux.org/)over Xandros. While both installations have the option to allow you to create a dual boot system and choose either the Linux Operating system or Windows XP, I have found Xandros to be more screwy. I recently tried installing Xandros on my laptop and it froze up at 97% installation forcing me to reboot the computer. The xandros never fully installed and did not work. I had to format my whole hard drive and reinstall Windows XP. I thought it was just me or my computer, but if you do a search on Google, you will find that lots of people experienced problems trying to install xandros on their computer and it resulted in messing up a lot of people's computers. On top of that the xandros free version open cirulation edition is very limited compared to other Linux Distros out there and if you buy the full version, you are paying for a lot of extras that you can get from other freely available linux distros. If you want to test drive Linux you are better of getting a older desktop or laptop(IBM hardware appears the most compatible with most linux distros), otherwise you will run into problems such as Linux CD burning not being supported with newer computer CD roms, newer computer sound cards not being supported, and newer computer built in wireless network card capabilities not being detected/supported by the Linux Distro.

Of all the Linux Distros that I have tested, I found the following to be the most user friendly.

ArkLinux
http://www.arklinux.org/

SLAX KillBill Edition v 5.1.7b
Live CD Only
http://www.slax.org/download.php

Puppy Linux
http://www.puppyos.com/

Damn Small Linux
http://www.damnsmalllinux.org/

Here is a nifty little Windows XP program that you can directly run from Windows XP to create a Puppy Linux Windows XP dual system system. The only problem that I found is that my sound card and wireless network was not supported, but since my wired internet connection was supported it was no big deal and a small price to pay for greater antivirus and spyware protection. As for the sound card since I could boot into windows XP whenever I wanted, I could still use Windows XP to play all my media files. Use this at your own risk. I did not create the program and cannot guarnatee it will work for you as well as it did for me as all computers and their hard ware are different. If you want to test this just be sure to back up all your data and be prepared to reinstall windows XP if things don't work out.

Here is the file you need to set up dual boot. Just install, run and follow the on-line instructions.
http://dotpups.de/puppy-releases/1.0.9-CE/installer-for-WindowsXP/
It is named: Puppy-XP-installer-setup.exe


If you want a full list of a
freely available Linux Distros that you can Monkey Around With to see which one you like best, go to:
http://distrowatch.com/

Best Regards.