PlugIn to allow users upload pictures and put pics in database

We are starting a wp site for a research project. The site will be used to gather data from participants. Data consists of answers to several questions posted in combo boxes, where participants select from available options. (pull downs)

Participants can then upload 4 pictures.

We are looking for advice and/or plug-ins on how to best build the site.

– Plug in to upload pictures efficiently
– solution for user friendly gathering of data 12 questions and pull down answers
– Registration page with customized fields
– Backend database that allows efficient analytics of all gathered data (participant info, answers to questions and pictures)

Any suggestions for plug-ins, tools, etc would be much appreciated.
Thank You
Vincent