One that I like and I heard leads to good conversations is the "Who lies more girls or guys?" In this case though it won't be used as an opener as this topic is for after you already have the chick. Anyways regardless of what SHE chooses, which will probably be guys, always respond with the opposite to keep the conversation going.
when she says: Guys: List of bullshit things guys apparently lie about
You respond with girls because: Age, weight, etc.
Keep it fun and cool though, don't be a freaking nazi about it, laugh and smile cause after all its like a friendly joke.
From here, a great transition would be to go into the 5 lie game.
Rules: Tell her you will ask her 5 questions and she has to LIE and get the questions wrong
1. Where are we right now (or any other stupid question)
2. What is your name (or any other stupid question)
3. (another stupid question) - But this time slower as if your running out of things to say
4. Say "How many was that" but act as if you have no idea, like you actually forgot. If she says 3 - you win!
5. If she says anything but 3 go "OH MY GOD HAVE YOU PLAYED THIS BEFORE?" really excitedly like she caught you in the act of something. She will probably will say "No" in this case look at her and just say gotcha or something like that.

Now the point of using this little game here is before you use it make sure you place a little wager but keep it open, "Lets make this interesting, if you win I owe you one, if I win you owe me one" (Something where it seems like you will ask her to get you a drink or something lame) This might help out later
Anyways that's my conversation starter. And for later, maybe when you take her home, (if its the first date) don't forget she still owe's you one (Dont be like you owe me a BJ or anything like that) But you get the point, keep it small. Have fun!