Woah, slow down there!
That bolt should be free, there's only about 5 threads in the captive nut. The bolt can be held in by the force being transferred to it by the wishbone, push the hub in while pulling on the bolt, it should come right out.
Edit: Missed the bit about the spinning nut.
There should be a sort-of cage around the nut, can you bend it back into shape, or has it snapped off?
That bolt should be free, there's only about 5 threads in the captive nut. The bolt can be held in by the force being transferred to it by the wishbone, push the hub in while pulling on the bolt, it should come right out.
Edit: Missed the bit about the spinning nut.

There should be a sort-of cage around the nut, can you bend it back into shape, or has it snapped off?