Heat149 said:
keeping your index and middle fingers on L/R 1/2
Wait, what? You only need two fingers to press R1/2 and L1/2, middle fingers never touch a shoulder button. You place your index finger in the groove of the 1 and 2 buttons, if you want to press 1 you roll it up, if you want 2 you roll it down.
Put her on a platformer, LBP is loved by people (except me) and all you have to do is move sideways and the odd movement to the foreground or background.
The controlls are as simple as hold right, press X and every so often nudge up or down.
Muscle memory will take over after a few hours, so instead of pressing X to jump her thumb just naturally presses a button which causes her to jump. Like PC gamers can instinctivly press the button they need to get the weapon they want, if you move from console to PC you will see what I mean.
After muscle memory is instilled in her hands bump up the game to something like a drving game, now your asking her to hold a button, quickly press another button, then back to holding another one (accelerating, braking, accelerating) and being more precise with a stick.
The very last type of game you want to put her on is an FPS, especially COD. Using every button quickly, while using the sticks to look around and move, combined with some peoples motion sickness is never a good place to start somebody.