Where I live outside of Dallas, TX, the mozzarella cheese choices available to me are limited, so it has been difficult for me to develop any particular expertise on the subjest of mozzarella cheeses. For example, about the only whole-milk mozzarella cheese I can find locally without going into Dallas is a whole-milk mozzarella cheese from Wal-Mart. Unfortunately, I don't particularly care for it, especially after having sampled quality mozzarella cheeses from Grande, Polly-O, Sorrento and others that I brought back to Texas with me on trips to other parts of the country.
However, as somewhat a generalization, mozzarella cheeses with low milk fat content will tend to brown more easily than mozzarella cheeses with higher milk fat content. In this vein, for example, I have found the Grande whole-milk mozzarella cheeses to hold up the best in my oven under normal oven temperatures (500-525 degrees F) and reasonably long bake times. For really long bake times, such as when I make certain cracker-type pizzas, my more or less standard practice is to use the mozzarella cheese in slice form and place the slices down on the skin (or pre-baked crust) before I put the sauce down. I do this whether I am using a whole-milk mozzarella cheese or a low-moisture part-skim mozzarella cheese. By using the mozzarella cheese in slice form and putting the sauce on top of the cheese, the cheese is protected and better withstands the oven heat, even for long bake times. This method also helps keep the pizza from getting soggy if a lot of toppings, especially toppings with high moisture content, are placed on the pizza. I have also used mozzarella cheese in shard form, and I have used the cheese cold right out of the refrigerator to slow down the browning process. I have even read of some members who say that they partially bake their pizzas and remove them from the oven toward the end of the bake and put the cheese down and return the pizzas to the oven to finish baking. As you can see, there are principles of chemistry and physics and thermodynamics involved in many of these measures.
I have also found that, with a few exceptions, house brands of mozzarella cheese tend to be of lower overal quality than the brands mentioned above and are more prone to premature browning. So, if possible, I would stick to the best brands of mozzarella cheese. One of the few exceptions I have found where I live is a store brand called Best Choice. It is a low-moisture part-skim mozzarella cheese but it is made by a Wisconsin cheese company that is one of the largest mozzarella cheese companies in the world.
You should also take into consideration the amount of top heat your pizzas will be getting. For example, if you are using a convection oven or a commercial impingement conveyor oven, where there is more top heat than you will get in deck and similar ovens, you will perhaps want to select a cheese that is relatively high in moisture content so that the cheese can withstand the high amount of top heat.
There are also other aspects of matching cheeses to the oven used. One of our members, scott r, who has sampled just about every type and brand of mozzarella cheese (and other cheeses) known to man, discussed this topic recently at http://www.pizzamaking.com/forum/index.php/topic,6687.msg57370.html#msg57370
. A general article on pizza cheeses can also be found at http://www.pmq.com/mag/2001spring/cheesey.php
. If you are a glutton for punishment, you might also tackle this piece: http://www.correllconcepts.com/Encyclopizza/09_Cheese/09_cheese.htm
EDIT (2/1/2013): For an alternative Correll link, see http://web.archive.org/web/20040606230957/http://correllconcepts.com/Encyclopizza/09_Cheese/09_cheese.htm