If it is for Music then there is only one option Apple! and if you do buy Apple Leopard is coming out soon! which gives you 4 desktops and if you want to make music on a Pro level there is a new Logic Pro 8 just came out and the price has been cut in half which is amazing! to around £320 and you get over a grands worth of state of the art plugins.Mac is virus free etc you will always be slowing your PC down with all that crap software you have to have installed etc PC's are good for games! but it is just a matter of time when Mac takes over the games as well so you might as well switch now like i did 3-4 years ago! Vista is just trying to copy Mac OSX! why have something that is trying to be a Mac when you can have the real thing! and have real power in your hands!
Apple - Mac OS X Leopard Apple - Logic Studio - Logic Pro 8