Hi Jim
If you are putting it on a laptop you can get the latest Unbuntu 10.04 Netbook edition from here. Download the ISO and burn to CD, then you can run it as a live cd to see if you like it and then install on your system. The install will create the necessary partions for you. All info at the link,tells you how to put it on USB also.Straight forward and easy to do, On boot up you get the multiboot menu, Unbuntu being the first choice. Just installed on a netbook with XP Pro and works a treat. Have a look anyways.
http://www.ubuntu.com/netbook/get-ubuntu/downloadCheers,HTH,
ticker