Ok when I start a new game Alduin never lands on the castle to interrupt the headsman, preventing me from doing anything. Is there something I can type in the console to initiate the script where he lands on the roof?

Start a totally new game. Don't load from any saves you made just before character creation. I had the same problem and the only way I managed to fix it was to watch the intro again and make a new save.

Thanks man.

I ended up just using a batch file and creating a new starting point for the game.