Hi larrynard and welcome to our community
I'm not being argumentative here, but I believe the options
pointed out by CatBandit will only apply to Spell Checking.
Assuming I correctly understood you, I think you are asking about
the language used when Captions are automatically inserted during
the recording process. To set the language for those, try the
following steps.
From Captivate, click File > Record/Create > New
Project. (if you are starting a new project - otherwise, if adding
to an existing project, click File > Record/Create >
Additional slides.
This should present the recording dialog. On this dialog are
a few buttons such as Settings, Record and Cancel. If you look to
the left of the Settings button, just above the "Learn more..."
link, you should see "Advanced". And to the left of that will be a
down arrow button that may appear to simply be decoration. Click
that down arrow button and a new area should open up and reveal a
new option labeled "Captions In:". I'm guessing it will say Spanish
here. Click the drop-down and choose English.
Hopefully this was helpful... Rick