I'm sure that xp theme won't be nearly as impressive as vista... By default it won't be able to do the translucency effects, it won't have the fadeout animations etc... If you want something that looks as shiny or shinier than vista that will run on your outdated hardware, install ubuntu or some other flavor of linux that has the compiz rendering engine. (imo compiz's effects are overall way smoother and more impressive than vista's)... Otherwise, if your computer is *almost* able to run vista, and you want to stick with an MS operating system, check out Windows Server 2008... I've found it to be rock solid stable, and free of much of the useless bloat of vista... My laptop stutters on vista home premium, but win2k8 runs completely smoothly. You can download a 180 day trial directly from Microsoft. It means you have to format twice a year, but hey, it's free!