Not far from the train station (walking distance) is the Portuguese (Ironbound) district. There are lots of interesting restaurants, bakeries, wine shops, etc. worth looking into. If you are into seafood, Seabra's Marisquera is the place I would go.
If you are in Newark Terminal C, there is a fantastic Columbian café in the left-most spoke of the terminal. This is down where the international flights are, but you can just walk down there.