How do I disable a module when Drush or the GUI doesnt work?
If you have access to your database, you can do it through there. 

You can see all the modules enabled with:

SELECT name,status FROM system WHERE type='module' AND status='1';


You can disable a module by setting it's status to 0.

UPDATE system SET status='0' WHERE name='module_name';


For more on uninstalling stuff via drupal's db.