I'm a pretty geeky guy who has played around with Linux many times over the years (starting back in the late 90's), hoping to get away from Windows. Frankly, I would love nothing better than an OS I could put on my parents' computers and not have to worry about them calling me a month later complaining about all the pop-ups and viruses they have.
Ditto. And that's why for the last 4 years when anyone asks me about my recommendation for a new PC, I tell them "get a Mac". Yeah, it's not completely free (as in beer, or speech), but it utilizes a lot of the open source projects we know and love, is UNIX, and lets both power users and newbies get what they want done without dealing with things they shouldn't have to (registry problems, malware, restricted multiverse repositories, and the like). Most people just want a machine to get a job done and don't really care *how* it does it, just that it does.
Windows 7 might be getting there, but I jumped ship with Windows XP and haven't looked back. Maybe someday Steve Jobs will decide to lock down Mac OS X like iOS, but if that happens, and the OS will once again becomes an obstacle to what I am trying to accomplish, I will look elsewhere.