Sounds like the chain has come off.
It`s located behind the cover on the left hand side ( as you are operating it).
The chain drives the cutting cylinder which in turn drives the roller ( by a belt located behind cover on right hand side).
If you have lost both drive and blades than check the chain.
If thats still on, it may be that something has jammed the blade and caused the woodruff key to shear which is behind the cylinder drive gear.
best way to check it is to leave the chain cover off whilst you run the mower and see where the fault is.
hope that helps.
jimmy.
July 2009