I'd show her the different apps like Skype, TED and the fitness app... just to show her that not only you can play new beautiful games but you can also communicate with her, educate yourself and keep yourself in shape all that with your tv snapped in the corner... how's that?

TED?

Graphics...

Ryse.

Best looking X1 game is still Ryse.  Best way to show off the rumble triggers is Forza 5.

Ryse's graphics are probably going to wow her! Just be prepared in case she barfs when she sees how god-awful the gameplay is!

Ryse. Easily the most underrated game of this gen. Stunning visuals, just stinning and pretty fun and sometimes challenging combat.

For graphics Ryse. THe gameplay is actually pretty decent on hard as well.

Tomb Raider is just a superb game so if you want the all around package you can go wrong there.

Forza if youre into racing. Very pretty game, and very fun as forza games usually is.

If you want to show gameplay off in general, maybe TitanFall.

Also Plants vs Zombie Garden Warfare. I said before on this site but it actually is one of the best looking games ive played thanks to the frostbite engine.

But as i said in the first line, if you want graphics over anything else, then Ryse is your choice.  NOt only is it the best game ive seen on xbox, but very likely the best looking game ive seen in general