You can change the selections at the "Record New ... >
Settings" dialog. But that doesn't mean your custom stuff will be
the new "defaults" when that button is clicked ... the system
defaults will remain the system defaults. The good news is they are
recognized by their filename, I believe, so ...
... you could change the system defaults to your custom stuff
by naming your customized captions to the same names as the system
defaults - replacing "Adobe Blue" with your own "Adobe Blue" and so
on for the rest of the actual default values.
Of course, before doing so, you would want to first rename
the original captions so you don't lose them entirely by
overwriting them.
Make sense?