A Tourist visa is given to those visiting India for tourism or other non-business related purposes. You should apply for a Tourist Visa only.
A Tourist Visa-on-Arrival for Some Nationalities is also available.
The GopherConIndia organizers are happy to provide an invitation letter if you need one; we do suggest, however, that you check with your local embassy or consulate, as requirements differ from country to country. Do apply for your Indian Tourist Visa definitely by mid Nov. 2014.