Okay I said I wouldn't reply - and with good reason. Look at the nonsense above about Macs. But this post isn't Mac based.
Anyway on the Linux subject, I think Ubuntu is a little overrated. I'm glad that one Linux distribution is finally having a big following in dekstop market, but in my opinion the Red Hat based distributions are much better. My favourite by far if Fedora.
http://fedoraproject.org/
Fedora 10 comes out end of next month and will be even better than the great Fedora 9. The Fedora website may not be as pretty as the Ubuntu website but the distribution is much better. Fedora is the best desktop OS out there in my opinion.