I used to have the first High School Musical album as my guilty pleasure, and I don't know why but I kept telling people about it. Nowadays I do listen to Justin Bieber sometimes and feel pretty guilty about it :P
I'm old, so to many on here probably most all of my musical taste would be "embarrassing", but I don't think anyone should be embarrassed by their taste in music. Music is so subjective and if a certain type of music or musical artist brings you joy and makes you happy, then go for it! Life is too short to deprive yourself of something you enjoy just because someone else might not consider it cool. I have quite a varied taste that includes rock, pop and once in awhile a few country songs (mostly older country)
So, that said...
my favorite musical artists are (remember, I'm OLD) Tom Petty & The Heartbreakers, The Rolling Stones, AC/DC, Creedence Clearwater Revival, The Cars, Neil Diamond, Rod Stewart, & Jimmy Buffett.