Developing social networking website for students

Hi , I want to a website for students having social networking features. like [login to view URL] can add friends. 2. reply. 3. share notes 4. post queries (like which institute is better for java ). 5. add pictures (if they are working in colleges they can share pics) Objective : "Connect students in place where they can help each other" I have searched with many forums. and got some ways about site development. 1. Using Wordpress and buddypress 2. Using Php and ajax 3. python and GWT 4. blogger 5. Spring and hibernet. there may be other ways. Language is not concern guide me which would be better in terms of money, site loading time, future enhancement, good looking, security. attach your previous exp. if you have developed previously same kind of web . price can be vary and looking expert. suggestion are most welcome.