All are equally known to organists as he was a prolific composer.
Handel's fireworks music
Im just guessing, but maybe Für Elise its very well known in piano
the Well-Tempered Clavier
gangnam style by psy
Messiah.
kinderszenen That is not it. That is not a word.
Kinderszenen
aida
Wagner is most known for his operas and music dramas.
Claire de lune
Moon River
it was Pop Rock