Okay, for the sake of my sanity, I'm just going to assume that the person above who put, "Who's Ray Bradbury?" was totally and completely kidding. Although, if you think the majority of your audience might be in on this hilarious little joke, then maybe that exact question could be your focus.
Actual suggestions:
- Even though pretty much everyone (the ones who have heard of him) classify Bradbury as a science-fiction writer. However, he himself claims that he considers Fahrenheit 451 to be his only true work of science fiction, stating: "First of all, I don't write science fiction. I've only done one science fiction book and that's Fahrenheit 451, based on reality. Science fiction is a depiction of the real. Fantasy is a depiction of the unreal. So Martian Chronicles is not science fiction, it's fantasy. It couldn't happen, you see? That's the reason it's going to be around a long time—because it's a Greek myth, and myths have staying power" [Gerken, et al., WeeklyWire.com; wikipedia.org].
Couple ideas there: What is it about Fahrenheit 451 that makes is about "reality" when it's individual elements (plot, setting, character) are clearly fictional? Why would Bradbury state that his "unreal" fantasy work that "couldn't happen" be the one he allies to myth and believes will last longer and have greater cultural impact.
Also, hardcore sci-fi partisans have insisted that the real reason to exclude Bradbury from the club is that only science/technology based stories qualify as true "science" fiction, whereas Bradbury tends to gloss over or out-right fudge the mechanical stuff. If you're any kind of geek you can natter on about sci-fi for three measly minutes so well that no one will even notice how much or how little Bradbury gets mentioned. If not, consider what Bradbury used in his stories about, oh you know, Mars and rocket ships and stuff, that gained them such widespread popularity in that genre? In other words, what was he giving the readers that they weren't getting from the more traditional sci-fi writers?
Finally, many of Bradbury's most well-known and well-regarded works use settings based explicitly on the small Illinois town in which he grew up. How does this nostalgic realism mix with the fantasy elements of his stories? How has the vividness of his childhood experiences influenced his writing? What does it add (hint: humanity, something the reader can relate to amid the fantastic)...