While I've been one of the most negative here about W8,
it seems to me the class of users you're discussing might find W8 easier. Of the applications you mention (email, word processing, web browsing, an image viewer), only word processing doesn't have a Start screen tile out of the box.
I just wish I could stop thinking of W8 in terms of previous versions of Windows. It would make my learning curve less steep if I didn't have a couple of decades of habits.
Few existing business programs are Metro-compatible, and I find the constant shifting between Metro and the Classic desktop quite jarring. However, users you describe can do most of the tasks you mention in Metro, and would rarely have to see the Classic desktop.