2003 VW Jetta - Rough start

I have a 2003 VW Jetta with 20000 miles on it. Over the last month, at idle there isn’t a problem. However, when I shift into R or D, there is severe shaking and the car feels as if it will stall. As long as I give it some gas, however, it doesn’t stall. Once I start accelerating, there isn’t a problem. Also, I have noticed that as the car is shaking, I lose the power assist on the brakes for approximately 15-20 seconds. Any opinions on how to make the car stop shaking and keep the power brakes?

I would check your idle rpm. Make sure it is set at factory spec.

There is no idle RPM on modern fuel injected cars that is settable. The computer itself performs this based on parameters it recevies from various sensors.