Monara is a light and fast operating system based on Debian 8 base, built on the Openbox window manager with #! tweaks.
Monara is offered to users as a continuation of #! on the new Debian 8 base.
It is a Live DVD. Test it before you install it. The Installer icon is in File Manager. Just click on it and follow the directions.
Debian 8 would be supported by the Debian LTS Team till April/May 2020, so all you have to do is periodically update and upgrade Monara using Apt-get. Debian is quite stable.