I often use ISO files (Live Linux cd’s, DVD ISO’s for video, DVD ISo’s for installing software.) In the past I have used tools to burn them or mount them.
Recently I have been using a simple tool called virtual clone drive (http://www.slysoft.com/en/download.html) It is very easy to use and does not consume that much resources.
In the past I have used Daemon Tools (http://www.daemon-tools.cc/) to do this but that is a large install and does use a lot of resources.