Win2003: Microsoft may be sellin’, but customers ain’t buyin’. Secure by default? I got this to say: fool me once, shame on you. Fool me 20 times, shame on me… it’s amazing how much FUD is oozing out of Microsoft on this one, especially given their really poor security record. If you’re looking to dump NT, the best thing you can look at is still Linux, because no matter what you set up as a server OS you will have to do a lot of tweaking and configuration to get good performance, and there will be a hell of a lot more people who can help you with configuring Linux than a brand-new, largely untested, closed-source system.