Just grab the source to hildon-status-menu. 1. The menu's width is an #ifdef and columns are just a property with it being explicitly set to "2". Of course, it may require a bit more work than that... 2. Just make it use GtkScrolledWindow instead of HildonPannableArea. Since they share similar ways of working, making it do so isn't hard as such.
This was on my mind too, I was hoping there was some configuration file which could be easily edited, such as a .xml...