Can't turn car off!

I started my car, the engine was running, but the gauges on dash were all at zero. Couldn't turn the AC on, couldn't shift out of park. I tried turning it off, and the ignition wouldn't budge, I had to turn all the way forward, (making the scratching noise) then I was able to shut it off. Tried once again and same thing. Tried 3rd time and nothing I could do to get it to turn off. Ended up pulling the fuse for the ignition to get the car off. Mechanic is saying the whole crank shaft has to be replaced and will be $425 parts and labor. Does this sound right? Any other ideas?