That "is" the default scene for PP-2012.

But you could set the ground to "wireframe" or "smooth shaded lined" if you want the grid pattern.

Can't remember if the lights were changed, too, but if you want everything as how it was in earlier versions of Poser, you have to open a new scene in an older version of Poser, save it as a pz3, open that pz3 in PP-2012, then make it the default scene in your preferences.