Some problems with rear derailleur and rear wheel

[xerxes]

Take a look here: http://forums.bikeride.com/thread-1868.html

I think you have the opposite problem to VJAB. On his bike the freehub was gummed up so that the pawls wouldn't engage with the ratchet in the freehub. It looks like in your freehub that the pawls have gummed up open, so that the whole lot is effectively bonded together. Try removing the freehub body and flushing through with degreaser to see if that frees it up.