Difficult, I read more fantasy than SF, but maybe some of Ian M Banks Culture novels might be useful as a reference to some of the SF tropes, plus they're good reads by a very literate author who also writes more mainstream stuff as Ian Banks. Asimov's books are always fascinating.

It's the super heroes in an urban fantasy that's a little difficult. Super heroes tend to populate comics. Maybe you could get her to read Watchmen. :-)It's a very dark and bleak graphic novel with super heroes in an urban setting.