DMXzone reCAPTCHA 2 is a Dreamweaver extension that doesn't need much explanation about its powers. There's almost no forms to fill out without it as it's a great way to protect them from spam and other automatically generated program attacks. As you already noticed, it's based on the Google CAPTCHA API so there's no escape.
Until next Wednesday you can get DMXzone reCAPTCHA 2 with discount and even greater one if you upgrade from the previous version. Make sure to login with your DMXzone account so you can see the proper price for you.