Image Captcha And Spam problems

[oalper]

I was using regular Image Verification with vbulletin, and have been getting tons of registrations from spammers, who usually sleep for a while and start posting porn messages... I tried banning all email domains for these users, but it kept getting worse.

Having been tired of this, I finally installed recaptcha on my site, which is supposed to be more secure. So, my questions at this point are:

1. Is recaptcha really secure? Will this stop these spammer accounts?

2. 20-30% of the time, it is almost impossible to read the words provided by recaptcha... Is there any way we can make it a bit easier for users, eg. give words that are a bit easier to read or make the reload button a bit more easy to see...

Thanks.