Do you know what Ubuntu's meaning and its philosophy is? That'll answer your question about selling it.
I can't say there's no problems, nor is it easy. But it was made to battle the monopoly of Microsoft and to truly try and develop an operating system where everyone can learn and contribute, and make their use of the omnipotent computer a better experience. It has almost everything any user can ask for.
I'm not saying it's the best, but still... for something that's free it sure has more perks than Microsoft. And best of all, it was designed with YOU in mind >_^ |