Please help me!!!!!!!!!!!!!?

I travel alot and i get really frustrated not knowing any language but English, i have picked up a few words in Spanish, Arabic, Finnish, french, Tamil and German but have never been really committed to learning one even though i like learning languages. Now i am so frustrated have decided to learn one fully, i will stay commited because i can use it in other countries and cultures. i go to all countries equally and have the same amount of use for all of them but i want to know which one is the most usuful and kind of easy, remembering that the ONLY language that i know more then 20 words of is English.