I am a huge fan of SQLite and it does have a GUI front-end, though I confess I haven't used it. Still, I'm not sure if this is appropriate for your "non-techies" needs. It depends upon whether or not "non" is in ALL CAPS.

On the other hand, I probably wouldn't let non-techies touch the database directly. Give them a gui or command line interface so everything that goes into the database is controlled by your code.