I'm not an expert on machine repair, but that is how you fill a bobbin on a Singer, too. You hold the outer wheel and loosen (righty tighty, lefty loosey) the inner wheel. To change it back to sewing, you just tighten that inner wheel.
I'm pretty sure there is nothing major wrong (you can't kill an old Singer with a stick), probably just needs oiling or someone put something back in wrong.
Someone better able to help you with anything beyond the bobbin winder will be along soon.
bkay