I'm probably just incredibly thick, but how do i tell which Mode is active on the NewMissions / ClassicMissions switch ?
Is it the currently displayed Text ? If it says "New Missions", is that currently active ?
Or do i enable what the Button says by clicking it ?

It's late and i'm dumb.

When it says "New Missions", then those are active. :-)

Those new missions are easier versions of some missions which were found too hard on the Floppy Disk release.
The classic missions are those hard ones as they were on the floppy disk version.