If you want to learn a lot of good practices and maintain and extend your codebase in the future, RoR is fantastic - but may be a steep learning curve due to all the new concepts and levels of abstraction involved, and is somewhat harder to deploy, and probably somewhat more expensive to host.
If you want to "hack something together quickly" to deploy cheaply on any of a wide range of hosting providers, PHP provides a famously productive way to make a mess^H^H^H^H simple web app.
If you want to learn a lot of good practices and maintain and extend your codebase in the future, RoR is fantastic - but may be a steep learning curve due to all the new concepts and levels of abstraction involved, and is somewhat harder to deploy, and probably somewhat more expensive to host.
If you want to "hack something together quickly" to deploy cheaply on any of a wide range of hosting providers, PHP provides a famously productive way to make a mess^H^H^H^H simple web app.