I’ve seen a lot of new users—and even kids—using Linux comfortably. And everything goes fine—until they decide to install new applications.
You see, in Mac people can install an application by simply downloading it, copying it wherever they like, and double-clicking on it. In Windows, it’s a matter of running an ugly installer, answering a few questions, and letting it copy a zillion files all over the place.
In Linux... it depends.