Near as I can tell using my Google ninja, Acrobat Capture is a utility that works in conjunction with scanners to scan loads of documents and convert them to searchable PDF files.
Adobe Captivate does vastly different things. Records screen activity, allows you to create Quizzing that links to a Learning Management System (LMS) and many other things.
Sorry, can't help you there. Prior to today, I had never heard of Capture!
I'm going to go out on a limb here and suggest that you might try asking the question over in the Acrobat forums. Maybe someone over there will have an answer.