Is that game computerized or on paper?
By the way, since it is random, there is no advantage in picking the boxes according to any kind of strategy.
The strategy we refer here is when to stop/by what logic to advance. I had the million in my box in the first 10 set of games, it is no big deal, you are supposed to get it 4 times out of 100...
The problem is that in real life you have only one chance (1 game to play), thus you are supposed to play according to your best strategy, so you can get the possible biggest win....