everything is on bc there is only enough juice to keep those things going but not enough to start the car.
maybe you need a new battery, or maybe top it off with distilled water and charge it. how old is the battery?
like you said checking the ground is a good idea and make sure they are tight on the terminals.
another thing to consider is the condition of your alternator, maybe thats what cause your battery to die?
i had this happen to me several times, the negative terminal wouldnt tighten down all the way so it would be loose and sometimes the car would click and then die. i would wedge it down somehow and it wouldnt happen that often but then one day i was making a u-turn at 3am and the car died i was like holy FCK i have no hazrds and my car is all black, in the middle of a crazy intersection. i immediately got out and pushed the ground back on which had came completely off and then i was on my way.
i left it for so long bc i was waiting to relocate my battery to the trunk