Bon Jovi will get any girl worked up. "Dead or Alive" is a good song for that. Easy to play and girls know it.

However, I agree with a lot of the replies on here that just playing some improvised scales can sound great. Crank up the distortion, and you can just play slow easy runs up the fret board and it will sound so soulful.

For guys who aren't fantastic singers I'd always recommend stuff by guys like Bob Dylan. First of all the chords are pretty easy but more importantly it's the kind of music where you can let your voice be terrible but if you do it with heart it sounds great.

For me personally I love having a Neutral Milk Hotel song in my back pocket. They're one of my favorite bands and there's a really cool community around them. They're not a mainstream band but they're at the tippy tippy top of the underground scene so a lot of people know them and are usually crazy enthusiastic about their music so you can form some special bonds with people that way, romantically or otherwise.