After downloading and installing RadRails, I was clueless about how to use it with InstantRails. I tried to use RadRails but failed completely. This made me leave RadRails and confine myself to using InstantRails alone from the command line console and the rudimentary file editor that comes with it.
Hearing about how convinient RadRails is, I thought of downloading the Ruby on Rails stack one by one by myself and installing it, first Ruby, then rails and finally downloading and installing MySQL then configuring them all and running them. But that sounded like a headache, after all InstantRails was doing all this for me in a single step.
I then, by accident, came across this clear and simple description of how to configure RadRails to work with InstantRails! Mission accomplished.