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Just spent an hour messing about with this game rinstalling drivers and tweaking settings to get it working so sharing the fix here.

When starting the game the intro video is messed up; It's squashed out of shape. The sound is fine though, the game is actually running but you can't do anything with it because you can't see. I had to Alt-Tab out to the desktop to quit.

The fix:
Our PC display is a strange resolution, 1440x900. The game seems unable to autodetect that and tries an inappropriate setting. You need to manually edit the following file:

As the name suggests it's a text file so Notepad will do. Change these four lines near the top:
ScreenWidth 1280
ScreenHeight 800
WindowWidth 1280
WindowHeight 800

Change both width & height setting to match your display, in my case that is 1440 and 900 respectively. The game (and my children) are perfectly happy with this and it just works.