My trash won't 'empty securely' as much as i try to delete the trash, also some items are locked and wont unlock. HELP !

Hi. What have you in the trash that is locked? Do you get item in use when trying to empty trash.If you are positive that it is not an apple systems app. You can take it out of the trash to desktop click on the lock and inter your password then put it in trash and empty it.If it is a running app you will have to quit or force quit the app. Or restart and try again. If it is an item that is part of a startup or login you may have to stop that to delete it. http://support.apple.com/en-us/HT201583

Hold down the option key and empty the Trash. Don't empty the Trash securely unless it's necessary. Remove any items that don't need that treatment first.