Re: Game hanging at F.O.B. during Priority: Earth
Maybe, you can try the method described in this thread.
The corresponding commands would be "Biop_End001 Priority" (without the quotes, start of the Earth mission) or "Biop_End002" (without the quotes, shepard injured wakes up on the citadel)
I think the first one will not help you because I assume the the jump point will be well before the conversation with the Major.
The second one on the other hand means that you will miss out on the entire mission and on some imho very important conversations.
So all in all I would recommend to use another save game that is older than that you're using now to make sure that the save game is not corrupt and therefor the culprit.
If that not works try to reinstall the game.