We need a little more information please.
The processor shouldn't make any real difference as to how you go about installing Ubuntu. Go to their website, download the latest image (10.04 LTS), either 32-bit or 64-bit, depending on your preference. Burn this image to a CD, and reboot your computer. Make sure the BIOS boot-order has your CD/DVD drive before you HDD. It's a very straight forward installation, and there's not a whole lot that can go wrong.
Sorry if I misunderstood your question, but that's what I took from it. Good luck