I could go on, but that's probably it for a start. I'd be interested in comments from women as much as men. Your mileage may vary. Remember that members of the opposite sex are people, just like you. Women aren't orifaces, guys.
Guys have feelings too, women.
One of the things that you'll come to find most attractive about a person of a the opposite sex in terms of a relationship is that the person is attracted to you. I have to give credit to a discussion in some newsgroup to this idea, but it really hit me when I read it. A market is defined in part by those people who want what you're selling. Not everyone is going to want what you've got, great as it might be. Not grin, but smile.