I have used both and crashed both. Linux, when well maintained and well setup is virtually crash proof. I like to play around with kernel driver code so I have been able to take it down but I assure you it was all my fault

Many people also crash it when compiling in new kernels (I am guilty of this too) because they throw in options that won't work with there hardware. I see linux to windows like c to java. Linux, like C, has no hand holding but is very powerful and is usually considered to be the guru's choice. Windows is like java, it has a lot of hand holding and won't let you shoot yourself in the foot as easily but it runs a little bit slower and lacks some of the options and power, or at least it doesn't let you get to as low a level (and actually manipulate the pointers it is using and such).
Win2k seams like a great stable workstation environment, probably better as a workstation then linux for now because of mainstream software packages. I still perfer linux as a server because it doesn't have any GUI overhead like Windows does and it seams to run "faster" and handle more users. I also think the remote administration of a linux box (or any other unix based os) is second to none. As long as you have a good administrator, I believe both can be very secure against hacking also, though I don't know much about how Windows uses advanced security features.