Simply, what is your number one goal OR what is your priority in what you'd like to do.
If you'd like to learn English and someone asks what your ultimate goals is, they are asking what your number one goal is for learning English - what is your TOP reason/goal.
Personally, my ultimate goal for teaching ESL is to teach English in Japan. I may want to teach in Italy, teach online, and develop a new ESL system... but... my ultimate goal - the one thing I want to do more than all the others - is to teach ESL in Japan.
Understand? I hope this helps! Good luck! :)