cheese

Question

I understood from the Pesach list that all cheese should be Chalav Yisrael. Is this specific to soft cheese i.e. cream cheese, or to hard cheeses as well, i.e. muenster, mozzarella, american, whatever they use to make string cheese...? Also, if one is away from home and cannot get the Halav Yisrael (especially cream cheese), would it be okay to use something with an OU/OK? I remember the Rabbi saying once that he doesn't know how Entenmann's gets an OU for their products that have cheese. Must we be careful about other products with cheese? For example, there is a products calle "dolphins"--fish-shaped crackers with cheese that have an OU/OK.