I find most people are hooked by a good story that can be translated into a short push for the book.
For instance, I wouldn't expect many folks to take a recommendation on Ghost World as it is hard to describe and to get people excited about. Watchmen, Understanding Comics, Maus, and many good starting points are hard to describe as something people would like to read. But it is still a fabulous book. Ruse: Enter the Detective would be a good book, but I personally think the beginning scene and entire first half of the first issue is down right confusing for most neophytes. I tried it on three people... they were confuzzled. Take a look at some of the leaps between panels say on the first two pages.
On the other hand, a book like Season of Mists (Sandman) is easily described as, "The God of Dreams, Morpheus, is tricked into taking the keys of hell by Lucifer himself and has to deal with it."
Or Stuck Rubber Baby, "A gay young man comes to terms with his sexuality during the civil rights movement of the 60's." This book I wouldn't recommend as the characters are tough to tell apart, though.
Or Concrete, "A man's body is transformed by aliens to Concrete and the world embraces him as a Celebrity. This attention and the situations it gets him into are more harrowing than any alien probing."
Or Whiteout, "The sheriff of an Anarctic research town has to deal with a gruesome murder. Cold, lonely and people are out to get you. Sounds like fun."
Or Torso, which is a great book and historical, too. Or Kabuki: Circle of Blood, "A lethal assassin in her own cycle she can't escape." Astro City Confessor series is quite good, "A Superhero is suspected of a series of serial murders."
Why not describe a few to her in this manner and see which she says, That Sounds Good, to.