I haven't flown jets either. (hoping to rectify that this year). Main questions they can ask you is generic stuff. eg swept wings, pros and cons of jet engines against props etc. If you have Handling the Big Jets by DP Davies then that should have most of the info you'll need to answer any jet type question that is fired at you.
Remember, you aren't expected to be a technical genius, they just want to see that you have a working knowledge of stuff and can answer questions truthfully and honestly.