Or at least, the most basic of options work, anyway.

-=-=-

Overscan can be changed between a 0 and 10% overscan border thing.
And the screen actually scales like it oughta.

SoundFX and Music volumes can be set between 0 and 10.
And the audio volumes actually now work like they oughta.

DebugMode toggle is working like it should.

And all settings are saving and loading correctly.

A whole bloomin' day, that's taken.

Tomorrow I need to look into getting multiple controllers and things like that working properly, and probably adding in options for Invert-Y due to the unique way that X360 controllers seem to work.
Stupid controllers. Grrr!