First allow me to explain why I believe Linux is teetering on the brink of mass acceptance. Of course, I'm talking here strictly about the technology issues. Whether the massed ranks of Linux distributions can match Microsoft's awesome marketing clout is another question entirely. And I'm quite sure that if Linux sales hit a certain threshold, there will be reprisals from Redmond. But let's look at how Linux for everyone might work from a practical point of view.
Most people get their operating system with their hardware.
Customers plug in all the various cables, flick a switch and, after a sometimes deafening musical interlude, they are transported directly to the Windows desktop. The Mac experience is similar. With the modern graphical desktops, KDE and Gnome, it's possible to offer even the rawest newcomer a start-up experience that is no harder nor in any respect more daunting than that offered by Windows. If it is really necessary, something can even be done to hide those scary looking start-up messages that roll down the screen during the boot process. But this can be done with the help of an introductory walk-though.