I want to create a "Human powered document processing" website in a formed as a gaming mechanic that will prompt volunteers to weed out text missed by OCR (optical character reader) The challenge is that the OCR output often contains errors and omissions, which hampers searches. Manual corrections is needed to weed out these mistakes, so that the text become machine readable.. I want to accomplish these task by splitting dull repetitive task into tiny microtasks and distributing then to register contributors on my site. I want to digitalized pedigree books into an online database. I want to recreate recaptcha and http://www.digitalkoot.fi/en/splash all roll into one.. Help!!!!

What programing languages is best needed to create a recapctch type website and is there any open source project similar to this I can use? I need a some directions to begin this project, so all and any help will be great.