I have worked with almost all of the OS's out there, from DOS, to WIN* (all variants), MAC way back before they went to the iMAC, to half a dozen of the *NIX's also, to include LINUX most recently with Mandrake. Every OS has its pluses and minuses, my employer has just recently switched to WinXP Pro, without too much trouble. The reason behind this is to drop all of their IBM RS6000 boxes, they were very slow and expensive. In industry, cost effectiveness is the bottom line. They replaced theses systems to go to high end workstations running all of our software on WIN platform. Everyone is much happier, except us guys who run codes on *nix boxes exclusively and we only log into the PC network to log our time and check email.
OS's are chosen with the bottom line in mind in corporate America. If I forced the company to go to LINUX and run everything on that system, our subcontractors who run WIN exclusively would scream to no end because of compatability. In my house, my family is addicted to Windows, I stay there because I have to. My Linux box only gets fired up on the weekends because that is when my wife and kids use the computer the least. In the last couple of weeks they have become addicted to Tux Racer, so I suspect that the Win box will be running less and less.
The bottom line is that people stick with the comfortable. If we were all forced into runing a command line at the begining, we would do it now. Mac and Win forced the GUI onto us and we liked it. When I run a *nix box, I run thru the command line, Win thru a GUI. Stabilitywise, I have not had problems with either, they run and run. Only when I surf the internet do I have problems with IE crashing, and only on certain sites.
My vote is for what ever you feel comfortable with that does the job at hand.