Casa Vieja comes under the heading "Local Joint." They serve Colombian food and I gave this place a try yesterday because I was in search of a new version of the Bandeja Paisa platter. (Photos and all are on my blog under "Aruba Local Flavor"; the photos are better than my explanation of this platter.)
The owner used to operate La Finca in Oranjestaad. Well, his Casa Vieja is an improvement on La Finca. I ordered the Bandeja and what arrived at my table a while later was exactly what I wanted. This platter of food is nothing short of massive but quantity is only one issue. The flavor was typically Colombian, the kind I like, right down to the hot sauce on the side.
As I said, this is a local joint and you'll run into plenty of Colombians and Arubans here at lunch time. Go early and stay a while for the people watching. The food is hearty and not for the timid but it is authentic.
Casa Vieja is located not far from the Codemsa. If you're at the traffic light by the airport, turn inland as opposed to going to the airport. This road ends at Codemsa. Turn left, drive a short distance, and keep looking on your left. Casa Vieja is there, before you get to the traffic circle.