Usually the interior light will go out when ignition is switched or when car is put into gear. Not always on this '98 SE ???

I guess you will want this post transferred to the Taurus forum....

Try Spraying Penetrant Oil Like Wd40 Or Twister On The Door Latches And Open And Close The Doors Several Times. That Should Loosen Up The Switch For The Int Lights In The Door Latches.