I take NJ Transit, the train pulls right in to the Convention Center.
Also, try the little lunch spot up in the train station area.
Family owned and operated. Good food and fairly priced.
Don't know where you are coming from, but the train cost is less than tolls and parking for me. Clean and comfortable and they always have a designated quiet car. I didn't even bring a jacket.
Just be sure to check departure times, as the later in the day, the more spaced out the departures are.