Classical:
Beethoven, Mozart, Johann Strauss II, Liszt, Rossini, Schubert, Boieldieu…
Spanish / Latino:
Gipsy Kings, Santana, Juanes, various salsa and bachata artists…
Metal:
Metallica, Nightwish, Luca Turilli, Lost Horizon…
Folk:
Various world and ethnic folk music…
New Age:
Yanni*, Enya, Kitaro, Karunesh…
*According to his Wikipedia page (click on any word in this sentence for a direct link to go there), Yanni doesn’t like the New Age label and prefers to have his music referred to as “contemporary instrumental”.