Tips to designing a web server

I am really new to web development so please excuse my 'noobish questions'. I am designing a simple iPhone app that will need to request and post text. I have PostGres runnning as the database, so I just need a simple web server that will handle 'GET' and 'POST' requests. I do not need a full web interface like Django, because I do not want to make a web app, just a simple web service. My biggest concerns are security and speed, so I was thinking of using Twisted Matrix, but I do not want to reinvent the wheel, so would this be a good option. Or are there better libraries out there?

Ps. Im using Python, but am open to any language. - Also, I want this to be production ready (so micro frameworks might not be the best)