For those that are more familiar, it's really hard to go to Mac's, even thought the mac mini is pretty cheap, quiet, and cool. It's a nice addition to the mac system. But yeah, xp all the way. It's what 90% of the world uses... lol.. but if you wanna be different use linux. Xp still isn't the best though... a couple things that mac and linux excell at: better application management. Xp sucks at that... seriously... mac and linux does it well. Then there's quick views of open windows. Get more than 7-8 windows in that small bar and you make mistakes picking them out... then there's 3d accerleration spanning multiple monitors... in windows if you wanna play, say, warcraft 3 on dual monitors and have half the game on one screen and the other one on the other half, you can't do it. But in mac's you can, and linix and is coming along. Also, there's easy-to-use standardized scripting, where a computer automates repititve tasks...mac and linux does it a lot better than windows. Lastly, there's comprehensive permissions enforcement. With xp, a limited user account can basically do squat... you can barely change your background. Linux does a much better job handling mulitlple user accounts, along with macs. Hopefully, these additions will be present in longhorn... anyone think this was helpful... props baby! lol... I spent some time on this....