The VG Resource

Hello! 
I am trying to rip characters from the game Hello! Project Battle Festival. A couple of the characters have been done so already, but I want to try and finish the character list my self. I understand there's no way to convert the file, and I will probably have to manually screenshot, but that is fine. Is there a guide for this process and the programs I will need?

I don't know much since I am a newbie, but I am completely willing to learn. 

Thanks!