Potential options for application langs:

• Node.js / io.js + Express + Browserify is the most simple and natural option but boring as am already doing this for the stuartw.io blog.
• Clojure + Ring + ClojureScript could be a fun option.
• Scala + Akka + Play is a bit overkill for this project.
• Python + Tornado isn't a particularly good fit.
• PHP + Silex would be boring for me as I've done it to death.

Requirements:

• Mainly front-end content
• Contact form
• Back-end admin (separate app)
  • List contact requests

Many writes, some reads, minimal updates, minimal relations which seems to point to some basic document stores.

Datasources:

• MongoDB is the most simple and natural option, but again may be a bit of a boring option.
• MySQL / MariaDB is a boring option and not particularly well suited to the task.
• Cassandra would definitely be overkill for this application.
• PostgreSQL would be more interesting but is a bit overkill.
• Event Store might be an interesting option, non-starter as it is written in C#. This can be run using Mono and they seem to support that, however, would rather use a Linux based technology.

Prototype in Clojure + ClojureScript