Strangers are usually boring and predictable for the most part. Don't expect the same conversation with two different people if you ask the right questions.
Person I Work With (Person A)---
Me: So...what sort of video games do you play?
A: I don't play that many. Maybe...Grand Theft Auto.
Me: Ah...I like RPGs and shooters. GTA was okay, but there's this other game...
A: Wait a second, what's an RPG?
Me: ...coughs after a long pause...uh...Role-playing game. So, the weather's supposed to get really bad later...
On to Person B, a friend of mine --
Me: What sort of video games do you want to play?
B: Maybe a racing game? I just finished watching like...all of Initial D.
Me: I suck at drifting in that game. If I wasn't poor I could practice more at the arcade.D:
B: <Insert name of other friend here> always kicks my ass. Hey, have you found <insert name of game> yet?
Me: I sware, I've been to every Gamestop, EB Games, and any other store you could possibly think of, and I can't find a single copy of <insert game here>.
B: I've got a copy, you know. Why don't you just borrow mine?
Me: Awesome! Do you want to borrow anything as a trade-off?
B: Sure, do you have <insert game here>? I got right to the final boss but the disc got scratched.
B: That sucks...sure, you can borrow it.
And so on and so forth.
In other words, most people are interested in crap music, crap games, crap tv shows, and crap in general. Holding a conversation is hard no matter what you're interested in. Just bring up whatever you're interested in with a bunch of different people; most of those people won't like the things you like, and the conversation won't really go anywhere. Still, there's always that one person that'll have your interests out of that group of tasteless scumbags, and that's the person you're putting out all your efforts for.
Anyway, that doesn't answer anything. Here's a list to break the ice:
"What sort of video games do you like?"
"PC or Mac?"
"Have you been watching <insert name of whatever shows you watch>?"
"So I read this book the other day..."
That's all I've got off the top of my head. Really, you just need to pick a topic that you won't mind talking about. Don't make the same mistake I did and talk about green tea ice cream for 20 minutes because there's nothing better to talk about. If it's not even an interesting topic to you, you might as well just shut up and spare yourself the energy.