Sorry, I don't have a schematic to your particular year so can't tell
anything for sure but could tell you what I'd do:

If I had to guess, it is probably an electrical problem of sorts.
Those systems (seatbelts, doors/trunk, etc) have very little in common
except power and ground so it could be that you have a ground loose or
that the power is not right.

If you have a volt meter, I'd check across the battery with the car
running and the headlights on. You should see about 14.5 volts. If you
see 14.5V, you know that the lit battery indicator is totally bogus and
it is most likely safe for you to drive it to repair shop.

If you see appreciably less than 14.5 volts, the alternator, battery or
wires/ground between is suspect. In that case, the car may leave you
stranded while getting it to your repair place since your battery is
truly not being charged.  In that case, I am not sure how that would
cause the other lights to be lit, though. (depends on how they
implemented these lights)

Hopefully someone here has a schematic to your year and will be able to
give you a hopefully more difinitive answer.

Remco