I had a whole bunch of problems with the 91.45 to 91.47 drivers. Several games using older shader models would either not run or crash to the desktop.
I then installed the 91.48 drivers, those solved all the problems at once.
http://www.guru3d.com/newsitem.php?id=4350
If your event viewer reports the driver stuck in an infinite loop you might also have some graphics overheating issue.