For PS2, it shouldn't matter too much what file you use, the .cue sheets aren't required by the Emulator, some games may require a cue sheet but that is different. So if it is an iso, bin or mdf it's fine. When it comes to memory cards, most people use Save States, so I did kind of gloss over it. On the real system, Memory Cards can need formatting. On the emulator in order to format it load up a game and try and make a save. It should ask you to format the card. I really only brought it up for legacy, but if you look at one of the check marks in the memory card menu, "Auto-eject memory cards when loading save states" makes using memory cards less of a good idea. So if you are using save states, using memory card might also be a bad idea.