3 Plugins I Recommend and Use

I recommend these three plugins below, and use them at all of my WordPress powered sites. They cut down/eliminate spam and bots on my sites.

Are You A Human – shows a game instead of a captcha which is almost impossible for a bot to solve – perfect to turn off that site security code which is easy for bots to solve!
WP Spamshield – stops spambots from commenting on your posts and you can show a counter to show how much spam has been blocked via a widget (and you can see the number on your dashboard). Also has a bot-resistant contact form! It’s also invisible to your users – if no widget, they won’t be able to tell it’s on your site!
No Page Comment – removes the ability of users to post comments on pages and custom post types as your wish – very handy to cut down spam and admin time

Hope these three help!
Nathan Pinno