Washing Machine Agitator Noise
Two main things worth checking come to mind.  The first is that the counter-balance weights are properly secured to the outside of the drum.  Sometimes these loosen up and make all sorts of weird and wonderful noises.

The second is that the bearings have failed.  The screeching noise you mentioned would make this more likely.  If the bearings have failed it is a very significant and costly repair - often the solution is to just replace the machine.

Either way I would recommend removing the top and front panel of the machine and running it to see if you can visually identify any problems.