The most annoying song?
'Sorry' Madonna (it's the most annoying thing I've ever heard)
'Hung up'
'Run it' Chris Brown (blargh that guy has a terrible voice and it looks like the song will never end)

The worst song ever?
I don't know, there are really a few

The song which other people might like, is probabley not really that bad but you hate anyway?
Songs that play at the disco, my friends love them but I see nothing in those musics, they're annoying and the same rythim during an eternity!