My apologies for asking such a stupid question, but I've searched and can';t seem to find the answer anywhere.

Is there a chek box to require that users have a vaid email address when registereing? And will need to return an email before their registration is valid?

It depends which version are you using. If you're using the latest version (3.x.x) then all acounts need to be verified by default. But if you are using an older version then there is a Host Setting under Login/Registration Settings to turn on/off Email Verfification