The Moon of Ducktales, no reason needed *The banger begins to play*
Super Mario RPG's final dungeon, Smith's factory, ominous music, eerie atmosphere, an at this point easy game finally turning on the monitor with foes that require thinking, the memorable final boss... *chef kiss*
Yellow's Lavander Town, played the game at 8 yo. but never got scared, in fact it reminds me of how much we respect Death in Mexico
Castlevania III's Castle Entrance, hearing Vampire Killer as we get into a mock of the first game's intro stage was a great surprise
Click Clock woods of Banjo Kazooie, some people dislike it for being too big, i find it is a great last level with a fun gimmick and a washing down to cleanse the literal and metaphorical shit that is Rusty Bucket Bay
And lastly Paper Mario 64's Star Road and Star Haven, a relaxing tune to lull you in preparation for a epic final battle in Bowser's castle, i have a second save state there just to open it and stay there listening the music