Bongo,
No disrespect intended here at all, but the general rule (in my experience) is 'tell 'em what they need to know'.
The problem is that if you tell the passengers that the 'left phelangie is loose', someone (with absolutely no technical knowledge) is going to decide that the left phelangie is a critical component.
They will then panic, and decide to get off the 'doomed airplane' (story will probably appear in all the tabloids). This panic will then spread, and several people will be uncertain as to whether or not they want to travel.
This will result in a delay (possibly major, depending on what part of the world you're in) due to baggage offloading, changes of manifest ..etc..
The ultimate result is that you miss an air traffic 'slot', the crew goes out of hours, or you waste enough fuel during the circus to require you to top up your tanks (which at some airports requires you to offload all your passengers).
I have seen all these things happen ...
Sorry to sound so critical, but this is a HUGE CAN OF WORMS !
250 non technical specialists in the back can ONLY complicate matters horribly ...