Playstation Vita VS PSP Comparison

Here you can see what PSP games will look like on your Playstation Vita.

In the setting menu screen, you can toggle bilinear filtering on and off, set the color space to PSP or Vita, toggle between rear and front camera for PSP games that use the camera, and set the right stick mapping.

The right stick mapping let you map the PSP's analogue nub, d-pad or action buttons to the Vita's right stick. For Monster Hunter Portable 3rd, you'd select the d-pad, which would map the game's camera control to the right stick.