What are songs that fit any of the scenes in Romeo and Juliet?
"Don't Fear the Reaper" by Blue Oyster Cult specifically references Romeo and Juliet, noting that the two lovers are "together in eternity." Another song is "Romeo and Juliet" by Mark Knopfler (of Dire Straits), which takes the perspective of Romeo, imagining an alternative ending to the story in which Juliet opts for another man. The best song of the bunch, in my humble opinion, is "Exit Music (for a film)" by Radiohead .It also evokes many of the themes in Romeo and Juliet, taking the point of view of a young man trying to elope with his lover. I recall reading somewhere that it was written for the soundtrack of the modern version of Romeo and Juliet, but it is on OK Computer.
Are you looking for specific scenes? When I think of the opening scene, I think of a song called “How Do I Live Without You” by Leann Rimes http://www.lyrics007.com/LeAnn%20Rimes%20Lyrics/How%20Do%20I%20Live%20Without%20You%20Lyrics.html . When Romeo and Juliet see each other at the party and try to decide if they each return the love, there is the play-influenced song “Love Story” by Taylor Swift http://www.metrolyrics.com/love-story-lyrics-taylor-swift.html .
"I've Got You Babe" by Sonny and Cher. This song is perfect for a pair of "star-crossed lovers."
How about "Check yes, Juliet" by We the Kings? This song is actually a take on the play, but has a much more modern feel than "I've Got You Babe," which is admittedly a little cheesy.
Taylor Swift's "Love Story" also alludes to a pair of lovers who sneak away to meet each other secretly.
"Love Fool" by the Cardigans. I think this song actually is used on the sound track for Baz Luhrmann's movie version, but it fits perfectly with Romeo and Juliet's love-at-first-sight moment.
"Glad You Came" by The Wanted. This song, with an innuendo that Shakespeare would have been proud of, would fit well for the scene when Romeo returns to Juliet's window to consummate their marriage.
Without being sure what you have on your list already, I don't know if you have included the Rolling Stones' song, "You Can't Always Get What you Want".
This chorus of this song is all about desiring the impossible, a definite theme of Romeo & Juliet.
Another idea: "Eight Days a Week" by the Beatles. This is a song making a statement about excessive feeling.
It would have helped if you had told us which songs you have, but some of the ones that come to mind for me are "Love Story" by Taylor Swift, because it actually mentions Romeo and Juliet, "Let it Be" by The Beatles, because it is a simple love song, and perhaps one I found from this list that seemed appropriate "When You Say Nothing at All" by Allison Krauss.
I'm probably showing my age here, but the first title that popped into my mind was a 70's song by 10cc called "The Things we do for Love." It's lighthearted and would be more amusing than serious, I guess.
Mark Knopfler's "Romeo and Juliet" is specifically about the couple, and they are also mentioned by name in "Don't Fear the Reaper" by Blue Oyster Cult. "Exit Music for a Film" by Radiohead is another.