I used Ubuntu 9.04 last year, dumped it for XP, since my PC's Warranty does not support Linux distros.
Dont wanna void my 3 year warranty :-)

But i can tell you Ubuntu is excellent, if you know how to use it , i.e
But there are blogs and forums you can learn from, so give it a try.
You can preview it without installing.

You can get the CD of Ubuntu 9.10 (Karmic Koala, aka Kubuntu) shipped to your doorstep for free. (anywhere in the world)

Just visit this webpage and follow the instructions.

Code:
https://shipit.kubuntu.org/
If you want to download it, visit this

Code:
http://www.kubuntu.org/getkubuntu
PS: Anyone using Sun Solaris ?