If people tell me real-world crypto is going to keep people in their seats, though, I'm totally down for that; it's a much easier talk.
I don't feel very comfortable giving advice about the direction of your talk; I can only speak for myself. If you have questions I highly recommend you ask the director of presentations. That said, personally I think the case in favor of DRM could be quite interesting since I've never heard a technical person argue in that direction. (At least not while doing more than simply assuming the token devil's advocate role.) If you make a good case you'll definitely get lots of questions/objections after!
* That the security goal of DRM is not about absolute platform integrity, but about meeting the commercial objectives of content providers, and that when you relax constraints from "absolutely protecting media" to "making sure titles are difficult to pirate during their new-release window to maximize profit", you get opportunities for interesting approaches to security, like renewability.
* That taken together, these two ideas suggest that DRM is actually a really interesting CS problem, and --- leaving politics out of it --- even if you believe it's destined to fail, it's worthy of study.