Another key point about buying souvenirs is that Red's comment after you purchase or don't purchase is always random. i.e. she might say "What a waste of money" even if you just bought a souvenir from a city you've already completed which might payoff at the next ball drain even at 1X.

I just point that out because I used to think she was helpfully coaching me, but she's not. Just ignore her.

It's not a real video mode. If you get a high score after that shows up, enter that code in the high score screen and it shows the credits. It's a joke from Dwight Sullivan whose previous game was STTNG. The code in RS is a joke where he's "revealing" the secret video mode in STTNG which was way not secret by the time RS came out.