Ultimate Ninja 4: Naruto Shippuden

To get 100000 Yen when you start a new game, have a Narutimate Hero 3 save on your memory card.

If you have a NH3 savegame on your memory card everyone except the following characters will be unlocked. This is how you get them.

If you have a NH3 save on your memory card you unlock all the characters except for Deidara, Sasori, Itachi, Kisame, Chiyo and the 4th Hokage.

To play as the stronger demon and kyubi forms (for some selected characters only), first unlock all the characters in the game (inluding the 4th Hokage). When in a character select sreen, do the following: hold R1 then press Circle to choose the character. You will be able to play as that characters demon or kyubi form.

In case you don't have a save game from "Naruto Hero 3" in your memory card, you can unlock secret characters by performing the stated tasks.