Did he even like Churchill, Stalin, de Gaulle, and so on? Did he have any personal friendships with them or was simply just acquaintances? Did he not like any of them? Is there one he probably liked the best?
This quote by Roosevelt on page 112 of "The sword and the shield" by Christopher Andrew says something about the way he viewed Stalin:
Winston got red and scowled, and the more he did so, the more Stalin smiled. Finally, Stalin broke out into a deep, hearty guffaw, and for the first time in three days I saw light. I kept it up until Stalin was laughing with me, and it was then that I called him "Uncle Joe". He would have thought me fresh the day before, but that day he laughed and came over and shook my hand. From that time on our relations were personal... We talked like men and brothers.
So I guess Roosevelt was a bit hesitant about Stalin at first but after a while he genuinely seems to have liked him. I'm sorry my answer isn't more complete, I'm no expert on Roosevelt. I just recently read the book and this quote was the first thing that came to my mind after reading your question.