I would like to create a GUI with a grid view; it would display images with names beneath them and tapping one would run some code. Would that be possible?
Depends what "some code" would be and how you plan to exit them (just turn off or you want to return to the GUI).
For the most part though there should be no trouble triggering your own code from a selection screen. It is when people want to start loading ROMS that things get more tricky.
I don't think he does, which is why he needs to start at the basics...I mean, I guess he's 13 and either: trolling everyone, 20+ and trolling everyone, or literally a 13-year-old who has dreams, but doesn't sleep,