AccursedTheory said:
Women aren't all THAT different than men.
An internet cookie for you for the most insight I've seen in months on forums.
Anywho, it's best to start with games that thematically match a person's non-gaming interests (and are well-made). Movies are a decent indicator, hobbies especially so, artistic tastes can sometimes be used as many games will try to echo those styles. While I could suggest that movie-based games are a way to go, too many are terribly designed and rely far too much on the player being well-versed in the movie to be able to progress without that outside knowledge.
One thing to focus on are games that are well-made as they will incorporate tutorials which teach the player how to play, a thing that is integral for someone new to gaming. It is also important to avoid doing the teaching yourself; if you're backseat playing the game, you may as well be the one with the controller and be demonstrating it because they're not likely to be learning how to play anyway. The most satisfying way to learn is often on one's own with a reliable source of answers such as an instructor.
Hopefully, you have a lot of patience, too. Gaming, like most things takes quite a lot of time to really pick up as a serious hobby or skillset. I've heard it stated that six months is the average time to effectively develop a skill in long-term memory, so if you're hoping she'll go beyond casual gamer, it's a must.
In the end though, some people just don't have the disposition for gaming, so you may want to prepare for that possibility. Note the word "prepare" as opposed to expect, never give up before long-term dedication and attempts have shown a result.