PHP and MySQL require to have a web server running. That means you will need to copy the code over to the client's machine and then run the web server locally still on the client's machine.
If that's what you want, look into the Microsoft IIS Express (here).
In short, IIS is a web server that can host and run a server side web application, written in ASP.NET or PHP.
Here are the steps you need to take:
- Install IIS express on the client's machine (one-time process, and I think quite acceptable - treat this as a runtime installation).
- Create a designated (hidden) folder for the source files of the web application that you want to deploy (one-time process).
- Create a windows batch file (bat or cmd) that starts the IIS (as described here) and then opens the website's URL so that the default browser starts. This file will serve as a shortcut, so you can place it on the desktop or wherever appropriate (one-time process).
- Deploy your web application to the hidden folder from step 2 above (repetitive process - deploy to the same folder when you want to upgrade the clients to a new version).
Please have in mind that I am basing my suggestion on your requirement to host and run the application locally (on localhost).
However, if there's an option to run the application on a separate machine (not a localhost), then you could simply place a desktop shortcut to the network or internet address URL that would open the default browser without problems.