I now have a database on it that I'd really rather not retype as well as a freshly installed Debian box. What steps are necessary to move the Windows MySQL database to the Debian (PortegeSQL?) server?

Migrating a database is as simple as selecting the database in the left column, clicking the Export link, and saving the database to a file.

This quick tutorial on how to install the MySQL database explains how to download and configure the MySQL Community Edition on Windows.