On the Display tab on the Options window you can check a box to Auto-expand box sets.  That will "open" all the box sets.

You can also turn off the nesting feature for box sets.  I don't have a screen shot for this one, but at the top of the list there's a bar with Total DVDs, Filtered and Sort.  At the far right of that bar is an icon.  If you click the little arrow next to the icon, you should get a popup menu with Nest Box Sets at the bottom.  Click that to un-nest your box sets.  Everything will be listed separately.