Songs, like pretty much everything else, follow Sturgeon’s Law: 90% of them are crap. So in order to qualify, it should be a requirement that the song was actually popular at one time. It should also be limited so that you don’t get to count stuff like “Mr. Tambourine Man, as sung by William Shatner”, which isn’t a widely-known version.
Here are my nominees for the “bottom 100” list:
Eve of Destruction
Seasons in the Sun
You Light Up My Life
Through the Eyes of Love
Shout (almost entirely because of the 15 minute section that goes “Shout! A little bit softer now…” ad nauseam)
That song where that goes “Lohuhuving yoohoo… OOOOOoooo ooo ooo oo oo oooo” with the “OOOO” part being that glass-shattering pitch from the Memorex commercials
I’m trying NOT to include songs that I hate mostly because of ubiquity, like “My Heart Will Go On” which wouldn’t have been so bad if it hadn’t been run into the ground deeper than the eponymous ship from That Movie.