What happens when the car quits? explain the situation please.
When was the last tune up made?
Did the "check engine" light come on?
What were the RPM's at before you put the car in gear?
What type of fuel do you run on the car?
I would check the distributor cap and rotor. If that looks fine, then I would have the ignition module checked. Autozone can check these for free.
I would check the battery voltage, both with the engine on and off, and I would also have the alternator checked.
Another good idea would be to check the neutral safety switch operation.(this may be the culprit) It may get shorted when this happens, or it is just failing.