Why is my ipod stuck on hold

Question

it is frozen on one song and not playing

Answer 1

The song is probably corrupted you need to remove it. Chances are you illegally downloaded it. : )  

Answer 2

It's just frozen, like a computer.

Try this: Push the menu and center buttons at exactly the same time. Hold them for three seconds, and your screen should go black, then show the Apple logo. It restarts itself and should fix the problem.