I don't know enough about the series to fully explain this answer, but I believe you are
Piccolo from Dragon Ball Z
Trapped in my prison, I await my release.
If I ever escape, I will make all men cease.
I don't recall whether Piccolo was "trapped" anywhere, but he certainly has the power to destroy all life on Earth.
Demon, Devil, both are my name.
Flute, bassoon, I am the same.
Don't know the first line, but piccolo, flute, and bassoon are all instruments.
My son will fight what we've become,
Together with God, they will be one.
Piccolo has a son called Piccolo Jr.
Piccolo is defeated by Goku, who is inspired by Sun Wukong and has a simian-like tail.
Freeza (pronounced "freezer") is the name of another Dragon Ball Z villain.