Videos
What you are looking for is a good JavaScript documentation generator. I found a decent one here http://apidocjs.com/example/. This will allow you to use just Express as OP asked.
Swagger isn't for generating docs, it's for making APIs. So you are going to need to learn a full system to get that feature.
I found a couple more here that I haven't fully looked into yet which seem promising:
Docco here JSDoc here and an article on Documentor for Node
Swagger is an amazing project for auto generating API documentation. It includes an Express module.
http://swagger.io/
https://github.com/wordnik/swagger-node-express
I'm just starting express and not sure what templating engine to use. any recommendations? Also, anywhere I can read about recommendation for doing stuff with express (like auth, code structure, interaction with db... etc)?