How does the Xampp/Moodle package actually install?
It does so quite easily. As a general rule of thumb, it does not usually write critical elements to the Registry. This makes it considerably easier to uninstall. A simple deletion is normally all that is required, and a step through the Registry deleting anything connected to Xampp will clean it all up. The MySQL installation, however, will create the C:\Documents and Settings\All Users\Application Data\MySQL\MySQL Server 5.1\data folder. This folder contains the database you create when installing Moodle. If you install, say, MediaWiki, it will create the database and write the tables in the same folder.