Tips for using CiviCRM on Amazon EC2
I'm not running Civi on EC2 but I am running other things on it and I can assure you it behaves just like any Linux server.

Personally I prefer Ubuntu to AWS Linux (it's one of the choices) - but Civi will run on either. I just like to use ubuntu because it's familiar and better documented. I use Apache web server (which you have to install using "apt-get") but you can use other web servers if you prefer.

My instance type seems to be "t2.micro" but I suspect it's the default - I don't know what it means, so I won't have picked it on purpose.

Takeaway message - no specific settings are needed for Civi over and above being a standard Linux server with a sensible web server running on it!