The setting screen shows advanced options the player can change. The initial values comes from the MISSIONS.TXT the [SETTINGS] section.
You will observe that whatever settings are first displayed during a gaming session for a given mission are carried over to any subsequent missions displayed (rather than the values for specific for the subsequent mission). It is not clear whether this is just a display problem for the second or third or nth selection or if the original values are also used for gameplay during the actual simulation despite which mission is launched.
Apparently, the work around for this problem is simply to launch the game and only play the first mission selected. If you find, you want to play some other mission, then exit and then launch that mission first and play it.