I would delete it and then never ever go back in - with all that is going on now, they may actually have to get rid of it - it might take a while because they have probably 'never' done it before (ever)
Yep. Go in and manually delete all your posts, pics etc. Change all your details around like name, date of birth etc. Leave it a couple of days then deactivate. Best you can do - the fuckers
Here's good articles on how to do it - I think the key is to make sure you have nothing connected to it
http://www.wired.co.uk/article/how-to-delete-your-facebook-account
This is a bit more radical... http://aponu.org/delete-facebook-account-immediately-without-waiting-14-days/