First of all, a note: my second target language is Russian but I haven't practiced it in years and I don't know many Russian songs/bands, therefore I'll be answering about my first target language, English.
Polish: do you have a favourite band/artist that sings in your target language?
Of course! Queen and Cher are my all-time favourites. Second place goes very probably to ABBA and The Darkness.
French: do you like musicals? What's your favourite?
I live for musicals. Really, they're basically my greatest passion. I have many favourites. First of all, everything, literally everything penned by Stephen Sondheim. Then there's the holy quartet:
The latter, especially, holds a dear place in my heart. If I had to discard every other musical and keep one, just one, it would probably be Hello, Dolly!, and not just because it was the one musical which started the fire in me. Edwardian/Belle époque fashion, grandeur, bright colours, crazy laughter, feel-good songs, not a moment of angst. And most importantly, joy, so so much pure joy. It's the musical I run to whenever I feel really, really sad, for whatever reason. I just love it like crazy, so much that it has turned me into the person I am today.
A special mention goes also to The Rocky Horror Picture Show, which my friends and I watched on TV during a New Year's Eve, waiting for the chime of midnight. We were 17 or 18 years old, I think. It is safe to say that we've never been the same again. :D