Sailor Moon has several songs for major battles that get you pumped up, including "Ai no Senshi" (the senshi vs the black moon sisters), "Moon Revenge" (the R movie finale), and "La Soldier" (the battle against Wiseman). Also, while the dub is what it is it gave us "Carry On" for the final battle of the first season. "La Soldier" and "Moon Revenge" come from the Sera Myus, which are just chock full of all the awesome music. Some of the best music you can find in Sailor Moon was never in the anime.
This song blends the lyrics of the DiC English theme with a translation of the Japanese theme practically perfectly.
"Sailor Senshi Reunion", which first plays as Sailor Moon goes to face Beryl alone with the other Senshi dead in the traps of the DD Girls. It's at first grimmly determined and badass, but at the 1:20 mark it descends into a real Tear Jerker as a sudden violin solo cuts through the scene like a knife that really tugs at the heartstrings.
"My Only Love" really makes the scene when the Moon Princess is revealed.
The original dub did this a few times. Even the most purist of fans admit that "Carry On", "My Only Love", "A New Day", and a few others fit the scenes just as well, and in some cases better, than the original.
The 90s dub's composer Bob Summers did have a good few cues up his sleeves that people who watched it growing up may never forget. Tuxedo Mask's Spanish guitar cue and Queen Beryl's/the villains' theme in particular will bring back many a fond memory.
"Mysterious Starry Sky, Part 5", a short, understated theme that tends to play when Usagi and Mamoru share a moment of connection as memories of their past lives surface. It's les than a minute in length, but it's memorable enough you'll recognize it when it plays from time to time.
Yet another example from the dub. Similar to "My Only Love", the scene where Jupiter recounts her first brush with love gave us "Rainny Day Man", a reflective and wistful pop song.
The Outer Senshi theme. You can expect badass moments whenever this song comes on. And the violin strings are clearly a reference to Sailor Neptune being a violinist.
The amazing rocked out soundtrack backing Rei's transformation.
Quiet Sorrow, the memorable track playing in episode 17 when Chibiusa remembers her parents while watching the interaction between Usagi's parents, then afterwards runs off and walks alone on the streets while it's raining.
Eternal Eternity. Finally, a duet between Neptune and Uranus. Very long-awaited by fans of the original anime.
Megumi Ogata, the original voice actress for Sailor Uranus, released a cover of "Moon Revenge" done alongside Masako Katsuki, the original voice actress of Sailor Neptune. This takes an already awesome song and turns it into a powerful duet about Uranus and Neptune's love for one another transcending time, and keep in mind the two of them never shared a song during the original run of the series. Twenty-five years later, and the two of them are still doing the voices of Haruka and Michiru.
Of the original anime's ending songs, easily one of the most iconic is the first ending of Super S, "I Want to Be Us" (Watashi-tachi ni naritakute), effectively the love theme between Chibiusa and Helios, especially played when Pegasus reveals himself to be Helios. And it speaks of the song's iconic status that it is the only song from the original anime to make the jump into the Crystal remake, as the ending song for the first part of Sailor Moon Eternal, the Crystal adaptation of the Dead Moon Circus arc. No, not even the de facto franchise theme song, "Moonlight Densetsu", had this honor (although it was used in the trailer for Eternal).