Zorin is pretty nice. I didn't do much besides load it on an old PC and poke around a bit. It seems to be a nice blend of Ubuntu (which I know nothing about) and Windows. It'd be a nice in-between for someone who wants to make the switch I think (it might even just be a nice one to stick with). It seemed to have all the stuff from Ubuntu that I don't understand (like using sudo commands) as well as the same general layout of Windows. I don't think you'd need to use any of the command line stuff but could if you wanted to.
Overall, I like it much better than any of the other free OS's I've looked at.