Q&A Human Verification works pretty well, or at least it has for my site. Go to Settings > Options > Human Verification Options and make sure "Register" is checked. (If it isn't, check it and hit Save). Then go to Settings > Human Verification Manager and click the "Question & Answer Verification" radio button and hit Save. Then on the bottom part, add some questions. In my experience they don't have to be hard at all, but some people say if they're too easy spambots will get past by guessing common answers (like numbers, colors, etc).

I have recatchpa on, I had Q&A on: Nothing changed.

What I don't understand is why emails are being sent when they register?

Hmm...are you sure it the registration that's sending out emails? If you have "Use Mailqueue System" set to yes you might have queued emails. On the admincp home page there's a "Number of Queued E-Mails" stat.

I have actually had registration turned off since about an hour and still had emails going out!!

Wow you are a genius! :)

How do I get rid of these?

ACP > Settings > User registration Options

1. Send Welcome Email
2. Verify Email Address in Registration

Also might want to look at:
https://vborg.vbsupport.ru/showthread.php?t=231715

lol, if I were a genius I'd know how to get rid of those. I don't know of any way except to go directly to the database and truncate the mailqueue table (but of course you might lose some "legitimate" emails if you do that).

Edit: I guess if the spam emails are all the same you could search for a keyword. Like if the subject has 'viagra' you could do this:

That was all already done.

I'm now interested in deleting the mailqueue!

up to you but it is the only way to stop the spammers registering on your site. I also see you have alot of bad bots spamming your site

Read my above post, its not relevant.

What I need is to delete the mailqueue!