This gets you over the choice of auto registration with potential spammers and the pain of manual registration. Now you get easy auto-registration, but then yoi sya if they get in or not.
I combined this with the 'SB Welcome Email Editor' plugin which lets you tailor the emails to give a great solution.
user gets email confirming registration but advising that this needs to be approved (using SB welcome email plugin)
I get email saying user registered with link to approvals area (added with SB...plugin)
Click the link, approve - job done
A great solution - thanks !!