As mentioned before,"Piratas Mall" is the most crowded usually,the fact it has a beautiful marina brings there lots of tourists who are staying in their boats and need a jump for some supermarket stuff.
This mall has a good supermarket (Zona Sul),a good food square only,with several restaurants(the famous in Rio "Bob's" sandwiches and the delicious "The Creps),besides,there is a 24 hrs money cash machine of Banco Do Brasil.
Angra Mall has some good options as"Da Bahia" shop and a cinema.
Both malls are about 3km from the city center and many bus lines can take you straight to there!
There are 2 malls in Angra with all you need as all the malls I saw before (ANGRA SHOPPING AND *DOS PIRATAS* SHOPPING).
The street for shopping is RUA DO COMERCIO,cross downtown city and you'll find all you need.