Now, why you want to do that? (virtual machines)

The other day I was talking to a friend about computers. I was telling him about using a virtual machine to run one operating system inside of another. I thought I was explaining it pretty well, then he hit me with the Why? question. Man I hate when that happens. My friend is a typical computer user, he only sees what he bought, a machine loaded with MS Windows. I don't know if its XP or Vista but that doesn't matter. He is totally unaware of the wider computing world out there. That there are other choices besides MS Windows has never come up in his mind. He uses at home what he uses at work and there is no need for anything else to exist. He has never installed an operating system and admits to not being computer savvy. He is a typical user.

So, just why would you run one operating system inside of another? Isn't MS Windows sufficient?
He is asking this of a guy who has been using Linux for a few years now. Of course the Linux is free answer is weak because you usually buy a PC with MS Windows already on it, seems free too. But in my experience you have to invest quite a bit of extra funds to acquire an array of applications to do every thing you want to do. Those Windows bundle package deals are mighty skimpy. Linux comes with lots of applications to do lots of stuff all for free. Still there's some major programs people cry out for that you can only find written for one operating system and not the other, like Photoshop and Incredimail. Besides this most computer users, like my friend, being creatures of ingrained habits, prefer to use MS stuff because they are used to it. So, the answer to this twisted why question is that I don't have to dual-boot anymore. Dual-booting is when you choose which operating system to start up when you turn on your computer. You can only have access to one operating system at a time with dual-booting. With virtual machines you can run as many operating systems as you have resources for. They will run as would any program on the computer. I could start Linux, (my habit) open a virtual machine running XP, start and use Photoshop and Incredimail. It seems to be the best of both worlds.
I know this is a bit extreme for the typical computer user, but being exposed to the wider computer world has open new possibilities.
Now to answer the question, isn't MS Windows sufficient? I myself have been using computers as a user since the DOS days. I have lived through the history of using MS Windows in various versions. Sure you could find programs to do everything you want to do in MS Windows. But, a history of blue screens, crashes and costly upgrades has not made me a very good friend of Microsoft products. This is besides the cumbersome licensing agreements and how they can check your computer to see if you pass the legality test. The endless security patches also help make me wonder about the quality and safety of putting Microsoft stuff on my machine. Since I have discovered and have been using Linux, I have little concern about the problems of using MS Windows. There are only a few applications for MS Windows I really use. I could get rid of MS Windows all together. Even though XP has been the best MS Windows yet, I prefer Linux. What about Vista? I will not pay for Vista. If I buy a new PC with Vista on it (seems free) I will take it but most likely I will build my next PC myself and install Linux on it. Maybe I will run XP in a virtual machine. Yes, it is wonderful to have choices.