Você é livre para escolher qual release do Node.js quer instalado em seu ambiente. Compatibilidade? Fique tranquilo, isso não será problema.
Bower is made by lots of people across the globe, contributions large and small. Be a part of it.
Grunt is a tool used to automatically perform frequent tasks such as minification, compilation, unit testing, and linting.
A generator is basically a plugin that can be run with the `yo` command to scaffold complete projects or useful parts.