I am also new to Unix, but I have used and installed both SCO Unix and Sun Solaris. SCO Unix is probably more Intel friendly. The newest to make waves is Linux which is growing ever popular. However there are many free versions out there on the web including Sun Solaris that you can download for free. I know this probably does not help you but I hope it is a start for understanding the easy accesability of different Unix varieties.
If you have a chance goto
www.techtv.com . They reviewed some Unix systems a while back.