"Pirates! Gold+ (Classic)" is like the original Pirates! but with "fancy images" and possible some small fixes/changes. Personally I prefer the original, which you can play with STEEM for example.
"Sid Meier's Pirates!" is the remake and I think it's even better than the original. It's extremely similar but with a 3D look, more minigames, more details.
The original Pirates! had afaicr only 1 code check and that was when you started a new game. I don't think the Gold+ version has that, but if it does, there would surely be a lookup pdf somewhere with the game files.
The check questions are actually related to the gameplay, as you have to enter dates for silver train/treasure fleet and these dates match up with their appearance in the game.
If you answered incorrectly not just was your starting position worse, but the whole game would become a lot harder/impossible - less (no?) crew to recruit, less (no?) traders (I think), bad health, pirate hunters instead of cargo ship prey ...