I tried to go off memory of what the default layout looked like—five total windows, with Info at the top spanning the full width of the screen, and then two columns with 3D view and Timeline on the left, and Outliner and Properties on the right.
It was easy to make the two columns. To make the Info window go all the way across the screen, use the hashes in the 3D view and Outliner windows to make Info bars right above them, then expand the left Info window all the way to the right side of the screen.
