Infinity Ward is aware of this issue of Ghosts booting to campaign mode and they are investigating. In the mean time, you can try this method if you wish, as it has helped some players experiencing this issue in the past.
1. Start from Home (press the Xbox button on your controller to go Home).
2. Go to My games and apps.
3. Highlight the content that you want to uninstall.
4. Press the Menu button on your controller.
5. Select Uninstall.
Insert the disc and allow it press X to install.