Ruby On Rails on Windows with Mongrel
You can follow this tutorial, it will get you setup you can actually manage your Mongrel server as a Windows service (start/stop/restart, start on boot, manage programatically etc etc):
How to setup mongrel as a native Windows service
I'm currently using this method to manage an instance of Redmine on a Windows box and it works wonderfully.
Good luck!
I have found the book "Deploying Rails Applications" very useful. Specially the chapter "Deploying on Windows". It gives you step by step instructions to deploy a Rails application using Apache and Mongrel
Rubystack is a free Windows Rails installer that we keep up to date and includes Mongrel support out of the box