Moderating Comments

So, this site has obviously been taken over by spam. And, deleting them is annoying enough (seriously, why doesn't Blogger have an option where you can just view a long list of all comments and delete 10 or 50 of them at once?) that I would like to move this blog to moderated comments status.

But, I am guessing that the word verification dealie is not accessible to people who cannot see the image, correct? Is there any way I can set this up so that I won't be preventing people with visual impairments from commenting? Any ideas?