Umm, ok, my mother who is 72 has never had to touch the command line interface in the three years she's been running a Linux desktop. While I'm sure you're right about 'most tutorials' - the ones actually designed for endusers usually come with pretty pictures and explain what to do step by step.
After 30 years of experience on PCs (including 24 years on Macs and 12 years on Linux), I am absolutely certain that most computer users would be much better off running Mac OS X instead of Windows or Linux.
Pretty awesome, 24 years. Guess you could say I was an AppleFanBoy too. My first Apple // is in a museum, my old Mac Lisa (changed to Mac XL after the lawsuit) is a clock at JPL, my first NeXT is still online and running (don't ask me how...), the //GS 'Woz' edition is being used to boost the height of a monitor, my first Mac II was a pre-production piece.
Eh, the list goes on and on. Basically, I've programmed in assembly on every Apple product up to the Newton. I've homebuilt Apple clones, and repaired Apple systems for six years (ahh, the fun of crackin' the case and grounding the flyback..)
Man, starting to feel my age, I guess. Anyway... I'm absolutely certain that most computer users would be better off running Windows 98, but since that legally can not be installed anymore (ahh, revoked licensing..), the vast majority can run a Linux install like Ubuntu (or even PuppyLinux) just fine.
Both have their word processors, their web browsing, their abilities to play music or videos, and most importantly - Solitaire, the most used application ever. Because people pay hundreds of dollars to play with virtual cards.
See, one thing that 28 years of dealing with endusers has taught me. What they'd like to do with their computer they'll likely never get around to. Now, maybe '78 was different, but today, people want to write Aunt Sally asking about that recipe, maybe check the television listings, watch that funny video on youtube that everyone at work was bragging about, and play solitaire.
Did you happen to know an engineer in Pasadena named Sam R.? He was an excellent Mac programmer. At JPL, he wrote an orbit insertion program for one of the old Mars landers. He was the chief software scientist at Polaroid last time I heard, but that was several years ago.
You are making your Mom run Linux? That's just downright mean, but the fact that she is going along with it proves how much she loves her children.