If you're not interested in updating (even though i would recommend updating) you can throw pictures that you have on your memory card as your wallpaper. Just view them on your psp then hit triangle i believe to bring up some icons and select set as wallpaper (or something along those lines)
Anyways, 4.01 m33 is a good firmware to update to
![Wink :wink:](./images/smilies/icon_wink.gif)