Awesome!! I have almost your exact setup and couldn't agree more. Vista has been rock solid on my desktop for 5 months. Leopard (mind you I have owned every Mac OS) has caused me nothing but problems on my mac book pro.
I am by no means a Kool-Aid drinking Mac fanboy like some of the posters who are insulting Aiden Shaw or Anuba..... but if you are having issues with Leopard what are you doing wrong?