- Angst? What Angst?: Mario (or Luigi) certainly doesn't have any qualms seeing Bowser get Stripped to the Bone after the first boss battle; they just say their end-of-boss phrase cheerfully and move on.
- Anti-Climax Boss: Bringing a Mega Mushroom to any boss will squash them in a single hit. Even the final boss can be defeated in two stomps!
- Awesome Music: This game's soundtrack stands out because basically none of it was used in later New Super Mario Bros. installments; the vast majority of tracks from this game were dropped entirely, and the few that did get reused were all rearranged and remixed starting with NSMBWii. A shame, because there are several great tracks in this mix:
- The Castle theme.
- The original mix of the overworld theme is pretty catchy.
- The Platforms-a-Plenty theme from Super Mario Sunshine returns slightly arranged as the music for the Trampoline Time minigame.
- The athletic theme, which was another track that did make it to the sequels.
- This remix of the Super Mario Bros. 3 boss theme.
- The unique melody used in Levels 8-5, 8-6, and 8-8, which was not carried over to any of the later NSMB titles.
- Game-Breaker: Against bosses, the Mega Mushroom will destroy ANYTHING. Even Bowser.
- It's Easy, So It Sucks!: A lot of people feel this way. Even Miyamoto has stated that he regrets making it too easy.
- Jerkass Woobie: Bowser. First, he gets a Family-Unfriendly Death by Kill It with Fire/Stripped to the Bone. Next, he's beaten Deader Than Dead as a zombified version of himself. Lastly, he Comes Back Strong anyway... just to get his ass kicked a third time (even worse if you beat Jr. first - and get a Papa Wolf rise from poor Bowser).
- Memetic Badass: Bowser. Not even death and Deader Than Dead can keep him down, apparently.
- Nightmare Fuel:
- The World 1 boss. When you jump on the button, it sends Bowser down to the lava, then swimming upwards, and burning alive to the bone.
- World 8 in general. A Lethal Lava Land Mordor that may as well be Hell itself, and the eerie music (especially after the second half of the world is unlocked) reflects this.
- Older Than They Think: The player character turning giant and destroying everything in their path first appeared in Bowser's sidescrolling level intermissions in Paper Mario: The Thousand-Year Door if he got enough meat from ? Blocks.
- "Seinfeld" Is Unfunny: At the time of release, New Super Mario Bros. was Mario's—and the video game industry in general's—grand return to the 2D Platform Game scene. Nowadays, however, it's often seen almost as rehashed as its successors.
- That One Level:
- 8-6. Vertical level with lava rising constantly. And the midway point appears early in the level.
- 8-Tower 2. This one has you riding a snake block with almost all the way. But there are so many obstacles in the way, and it can particularly get annoying when you are trying to grab all three star coins. Of course, you have to ride the snake block, or else you will die.
- Underused Game Mechanic: The Blue Shell is fun to use due to its defensive capabilities and shell slide (also, nice to have the Blue Shell not be the object of fear and hatred for a change), but it appears far too infrequently (while there is an enemy that drops it, said enemy only appears in a multiplayer stage), and none of the stages are really built around using it. It's also one of the few powerups that hasn't appeared in any other New series games, though the Penguin Suit is a Suspiciously Similar Substitute.
- Unexpected Character: If you decide to go through every world in order, then besides Bowser and Bowser Jr., the bosses are all new. In World 5, the boss is Petey Piranha. He's a Warm-Up Boss in almost every other game, and is the ice world boss, which makes it all the more unexpected, since plants and ice usually don't go together.
- Win Back the Crowd: Up until the release of New Super Mario Bros., 2D platforming games were mostly relegated to indie PC games. With console gaming, platformers in general were starting to fall out of fashion. 2D platformers were all but dead and the number of 3D platformers considerably shrunk. NSMB was such an unexpected success that Nintendo decided to release a Wii sequel. That one was also a huge commercial success and led to 2D platformers returning to the mainstream in the console market.
YMMV / New Super Mario Bros.