Had the same hanging problem when I tried to install InDesign and Photoshop CS5 5 on two iMacs (both 24-inch, early 2009 models with 4GB RAM) that I have formatted to install El Capitan.
From a tip I read somewhere, I installed Java that I downloaded from this link: https://support.apple.com/kb/dl1572?locale=en_US
You have to restart the computer after installing Java. InDesign installed without a hitch after that. Photoshop hanged twice on one iMac but on the third try, after another restart, Photoshop successfully installed. 
If this remedy failed, I would have tried the solutions mentioned here: http://apple.stackexchange.com/questions/208730/installation-of-adobe-creative-suite-6-hangs-at-adobehelp-on-mac-os-x-el-capitan