Robert A. Heinlein has a selection of rough and tumble reads that are a detailed social commentary. Starship Troopers, for instance was written in support of his views upon the need for a type of nuclear godfather in the world...this might still be an interesting discussion point with the third world arms race that is undergoing. For a change of pace, Stranger in a Strange Land explores our ideas of the whole judeochristian mythos as examined from the perceptions of an outsider, and the nature of love and compassion.
My other recommendations for a new science fiction reader are Isaac Asimov's Robot series, and the usual selections from Ray Bradbury; Fahrenheit 451, which explores censorship and personal liberties, Something Wicked This Way Comes, with its exploration of the worth of the life of an individual, while I Sing the Body Electric and The Illustrated Man are two short story collections. As these are given as a sort of science fiction introduction to children by schools, they should be suitable.