I've personally trained elementary school kids on the use of a distinctive version of Puppy not at all like XP Pro and they make the transition with relative ease and a short learning curve. The key is to have all the apps contained in the distro working properly and intuitively, and hide the technical complexity of Linux.
You can achieve desktop simplicity in Linux without having to emulate MS - just ask Apple about that. I also have corporate users that I've trained on Linux in a matter of hours and they don't seem concerned at all if things don't follow MS standards - it also help that I mention the fact that it's dramatically improving our bottom line!
![Smile :)](./images/smilies/icon_smile.gif)