That's probably what mine would do too, but I almost always have other windows open. But as far as I know the compatability mode change (to windows 2000) fixed the white screen problem.
I am still left to wondering about that render time. It's not typical for my computer (thought I haven't tested something as complex yet), but there must be something in my scence making it take so long.
"We don't actually need to know that the main character has a past. All we need to know is that he has an objective and a lot of people are going to die and a lot of innocent inanimate objects are going to be destroyed and blown up before he can complete that objective."