I'm not sure it is, to be honest. It's not well served with user-friendly configuration tools, so if (for example) your graphics card doesn't get set up correctly during installation you're up a gum tree. Also it uses the Gnome desktop by default, and in my opinion a novice who is used to Windows will be more at home with KDE. With this in mind you might try Kubuntu rather than Ubuntu, but the configuration comments still apply.
The two distros which stand head and shoulders above the rest for ease of use are Mandriva and SuSE. Both have comprehensive GUI control panels for configuring just about anything. The downside is that you need to download a DVD or several CDs to get the full experience. Mandriva 2007 is on the cover DVD of the current Linux Format by the way, so that might be a good place to start.
Eric