My wife was a minimal / non-gamer. I got her into WoW when BC launched (happen to time when she was recovering from a surgery). I think the key was that we started out together. I created a new character to match with hers, took the time to walk her through character creation (she takes a *lot* longer than I do), and then we hit the ground at Level 1.
She had a *lot* of questions, including things that you would never think to question as an experienced gamer. I remained patient and took my time to explain. I'm sure other players were wondering what the heck we were doing (I'm might diverge for a bit to show her something or how to do certain things) at times, but she picked up things quickly enough.
We played together pretty consistently for several days before I had to go to work, and by that point she understood the game pretty well and could do things with other characters (we kept the initial characters together all the way to max level) when I wasn't able to play.
We ended up getting along with another person and eventually formed our own raiding guild that was rather successful. She wouldn't top meters, but she understood the game well enough to be very good about minding her activities (e.g. keeping her sheep cc'd, not pulling threat too often) which was rather valuable in those days and the success of the guild overall was as much a credit to her as to me and our friend.
I think the big secret is to not get impatient. Take your time, enjoy the game, and show her interesting things.