Preoccupied with 1985...

Super Mario Bros:
Only Fire Mario can unmask King Koopa!
Using fireballs will reveal various foes posing as Bowser...

 Oldschool Mario kicks ass! Sure, new Mario games are epic adventures... But the original games are classic. I was playing Super Mario All-Stars for fun, and somehow got hooked on the original Super Mario Bros, and ended up playing through the entire game.

(View Screenshots Photo Album)

I recently discovered that even on the original NES, defeating any of the Bowsers in the first 7 castles with fireballs will turn them into various enemies before they fall into the lava pit... The very first Bowser turns into a Goomba, while Lakitu is the real boss behind castle #5. I can't believe I never knew this...

The backgrounds and graphics were also updated in Super Mario All-Stars, with a fortified castle wall serving as an appropriate backdrop for World 8-3, right before Bowser's castle.
 

Complete Super Mario Bros, and the Princess sends you on a "Second Quest". (Basically the same adventure all over again, the game has replaced all Goombas with Buzzy Beetles, and Koopa Troopas now move quicker.) In the Super Mario All-Stars ending of the first Super Mario Bros game, after defeating Bowser Koopa, a Super Mushroom falls from the sky so that full-sized Mario can share a dignified kiss with the Princess... (Kinda like the Mushroom Kindgom equivalent of Viagra...)

The Super Mario All-Stars ending has the Princess is dangling from a cage over a lava pit, with a slight update in text. It's about time we got a room, Princess...

(View Super Mario Bros: Screenshots Photo Album)