99 Jetta GLX has A Starting Problem!! PLEASE HELP

A week and a half ago my check engine light came on. The next day my door panel fell off. As I was driving down the street my check engine light mysteriously went out. The following day I went to start my car and there was nothing. The lights worked, but nothing else did not even my alarm system. So I had tried to jump it, but no such luck. Needless to say my car as been in the garage since than. Whats really bothering me is that my mechanic (for 10 years) is boggled. He has been in business for 30+ years and he has not a clue. Someone please help.

So the car died and will not restart and the battery is ok and the alarm does not work. Does the little red light on the driver front door blink? If so is it really fast or every second?