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?

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

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.