I recently received an old PC that had XP and I've scrubbed it and re-installed XP on it. However I now realise I am not going to use it for anything (seeing as I have my own laptop) so I figured I would play around with Ubuntu. I saw an older thread on here and people were happy with how it runs. So I plan on downloading and running and seeing how it goes.
It's a fine OS, and the machine I use most now. There is a (slim) chance that the GUi now't work when you first start it- an X setting has to be changed, probably fixed by now, but I had that problem the first day of vsn. 10.10's release. If you decide to install it on your HDD, partition it and leave XP on there as a dual-boot machine. As good as Ubuntu is, there are some things in the world that only Windows can do. If I were still interested in recording I'd give UbuntuStudio a try.