Vista was really pretty... But it's engine was struggling from day 1. It had compatability issues for months after launch. XP was Classic, IMO it was their [Microsofts] most reliable OS ever, with the exception of Win2000. Linux is awesome for hacking, it's free and you can program easily on it too, OS X is very sleek, but you can't legally put it on anything but a Mac, which are at a premium in price anyway... For you, I'd recommend Windows 7 (32 bit upgrade if you have less than 3.5 gig of RAM)