Windows. A lot of people will tell you that a unix-like OS is good, and/or you should use a Linux, BSD, etc., but don't listen to them. Windows is the most stable, innovative, user-friendly, and capable operating system.
Linux, for example, is deliberately difficult, in a desperate attempt to make the people who have no life, look like they know what they're doing.
And, BSD was originally made by a teenager, who (for what ever reason, I don't know the details) was jealous that _he_ wasn't the one who invented Windows; the project then grew by more people who felt the same way.
The stories are mostly the same across the board.
Think about it, Windows doesn't have 99.9% of the OS market share for no reason.
And with 8 being released soon, MS is upping the ante even more. Save yourself some headache, don't learn the hard way. Stick with the OS that's been proven.
