Is Drupal appropriate for what I want to do? I am building a simple portfolio site for a friend. The vast majority of the site will be static, but I'd like to implement a kind of news/mini-blog on the front page, just two divs where he can update the site with his latest news.

Is Drupal overkill for implementing this kind of thing? Moreover, how simple would it be to set up; I have no CMS experience whatsoever.
f you don't have any plans to expand the site in near future, then Drupal is an overkill.
The whole system is just too big for your purpose, and offers lots of functionality your friend won't ever need: permission system, roles, user profiles, content types, fields, forum, and comments. Especially as you don't have any CMS experience, Drupal will take the most time to setup, and you will need to learn a lot during the process.

I suggested WordPress because it is generally used for such websites by designers, takes less time to setup, and there are much more available themes and non-developer user tutorials. IMO, this would be the fastest option to setup.

Lastly, a custom CMS might be the best fit for this. If you don't have any ideas what to use, take a look at these frameworks: Codeigniter, Laravel or Yii.

Or, if you want to make it fun for you, use some micro framework: Flight (PHP 5.3+), or Slim (PHP 5.2/5.3). Pair it up with some tools/libraries for ORM/AR like Paris and Idiorm, RedBean, and/or an "unframework". If you want to get really fancy, add an MV* JS library like Backbone.