Henry Mancini is a good pick.
I am not convinced when it comes to melody quality of Hans Zimmer. First examples from his book are usually PIRATES OF THE CARIBEAN (written by Klaus Badelt) or THE LION KING (based on Elton John songs) or the song from Gladiator (co-written by Lisa Gerrard).
But my favourite tune smiths in movie soundtracks are more or less John Williams, Elmer Bernstein, early Alan Menken, Miklós Rózsa, Ennio Morricone, Joe Hisaishi, John Powell, Ryuichi Sakamoto, John Barry and some more.
And there are composers who undoubtedly write memorable tune. But I don’t really resonate with them. Like Maurice Jarre, James Horner, Jerry Goldsmith (he wrote some great melodies, but nor for successful movies), Danny Elfman, Franz Waxman. Several melodies from these composers have grown on me over time. But the hardly ever immediately click with me.