just to make sure i understand correctly, when the reset button is pressed, you want to update every record in he table where the EmailList = Y to N?
for this you don't need to use a multiple record update, use the single record update instead.
set the trigger to happen on submit button pressed.
for the Key column, select the EmailList column, set the Value to Y
then on the second page of the update record behavior, set the value for the EmailList to N