Oh, okay wow. I thought you guys were trying to tell me that you get to the inventory by selecting the main menu button.
and I was like Duh!.

But you DO page up/down with Main Menu button pressed down AND use up/down. nifty! Sorry for the Derp! moment lol

Still wonder what the left/right D-pad is trying to accomplish?! it seems to do page up/down to but does so very inconsistently in it's spacing of page up/down. Ah well. Thanks for the answers!