If you really want to be safe, uninstall windows and go with a different OS, or better yet just go Mac and never go back.
This is a good point. Apple OS X is essentially BSD Unix with a very nice interface, thanks to Steve Jobs and the NeXT way of thinking he brought back to Apple.
But, if one is doing garden variety computing getting a mainstream Linux distribution (Red Hat, SuSE, Mandrake) will do the job and the hardware is one heck of a lot cheaper than the Apple solution. To my knowledge, OS X doesn't run on Intel hardware (Darwin does, I think but there's no interface) while Linux does.
But if there are some apps that you must have and they are Windows, get a copy of VMWare and run it on a Linux system.
Voila, problem solved. Have a nice day.