I’ll have to echo what Dave said…
If you want ease of use, plus unix (real unix) if you want it, then go for Mac OS X.
Most people will never use bash or X11 in Mac OS X either, but it is there if you want it. So is Microsoft Office and Photoshop and World of Warcraft and iTunes and iMovie and Shake and Garageband and Doom 3 and all the other good stuff.
I use the command line pretty much for everything, but man, the GUI in Mac OS X just rocks compared to anything on Linux. Linux is GUI by committee, which doesn’t always work very well.
Don’t get me wrong, I love linux and use it exclusively for servers, but it won’t be on the desktop until your average joe can run it. That’s the problem we geeks don’t seem to be able to see.
We are not average, we can compile something, run vi to edit a configuration file, whatever. 99% of users can’t, and really don’t care. To me, that’s the beauty of Mac OS X. You can do all the geeky unix stuff if you want, but if you just want to run Microsoft Word and Firefox, you don’t need to bother with all the crap.
If you want to argue price, then I just say that Windows and Linux is only cheaper if your time is worth nothing.