Okay, so the arcade machine itself is up and running now. Eventually fixed the button problem after replacing the ground wire.
Ordered a new Pi 3B+ from Pi Hut and they've sent me the wrong one. Then they tried to blame me for the mistake. Nice.
Anyway, that means I need to wait for the refund and then get another one.
I'm not sure why chopperthedog was so negative about the Pandora, it seems to be working fine so far. Lots of duplicate fighting games and the controls aren't set up right in some games, but overall I'm impressed. Over 1000 games for £35, that's not bad.
Just need to go through the list of games one by one and get rid of any adult titles. I know "Bubbles 2000" has topless pictures, my mum popped over, had one try and that was the first game she picked!
So, now you know what I'm up to I'll stop commenting on this thread. Nobody seems to be reading it anyway