The South African Military History Museum in Saxonwold, a district in Joburg.
The 'Butchers Shop' in the Santon Mall (Superb Steaks ), 'Late Night Als' in Rosebank for 42oz plate of ribs. The Wanderers if there are any Cricket matches on.
Drinks ? Castle Lager is quite drinkable. Security - Don't attempt to walk anywhere and only carry what you need. Leave your watch and wallet in the hotel safe. Only take a cheap camera.(our local supermarket is selling 12.2 M pixel for £72). Avoid confrontation at any cost. Downtown Joburg is a no-go.
A really great place if you keep it safe.