help with spam

hi i m new to elgg and love it but the problem of spam on elgg nags me

i have seen these plugins

http://community.elgg.org/pg/plugins/project/688534/developer/vazco/text-captcha

http://community.elgg.org/pg/plugins/project/656224/developer/webgalli/antispammer-for-elgg

http://community.elgg.org/pg/plugins/project/384430/developer/brett.profitt/uncaptcha

http://community.elgg.org/pg/plugins/project/529826/developer/quiklink/recaptcha

but are these pluigns capable of preventing spam as i donot want my users to be spammed also which is the best has recaptcha been abondened for elgg1.7.7 and 1.7.8 as ot seems to be the most promising with backing from google need help fast