Does my clutch need to be replaced?

My car has been making a whining/screeching sound whenever I step on the clutch. I drive a 2005 Chevrolet Aveo and it has 104,000 km's on it, and the clutch has never been replaced. Tonight, my car started fine but it would simply not go into gear. Does my clutch need to be replaced? My dad told me that it was likely the release bearing (or throwout bearing) but I'm not sure.

I'm also wondering what kind of damage this would do to the transmission? RE: having to force your car into gear?