The Yeast Problem

I made whole wheat naans yesterday.
And they were great.
BUT the yeast gave me a lot of trouble. I had to use 3 packets of active dry yeast till I finally got it right. And I decided to go ahead with the last try simply because I was out of yeast packets and too lazy to go out and buy some. The first 2 tries were total disasters. The yeast just sat there mixed with milk looking like sand granules mixed in, only that sand would sink. The yeast refused to froth and become bubbly as promised. I had kept it in warm place as required. Maybe it was the temperature of the milk. All over the internet it says "warm" liquid. Could you please define WARM? The yeast manufacturer's website said 110-115F liquid. Now at that temperature you cannot drink liquid so how can that be warm??? For me, (and I hope many other people too) warm means drinkable temperature.
Then I realized I didnot have any cooking/candy/liquid thermometer. So I went ahead and borrowed my duckie's thermometer. It showed fine till 107F then started beeping. Which meant a good, high temperature for me. Then I added the yeast and mixed it well. Kept it near the oven to let it "froth" which it did not. After 15 mins I gave up mainly out of boredom and mixed it with my flour. Covered my dough, checked the clock, kept my fingers crossed and decided to check again after 1 1/2 hrs, just because then it would be too late for dinner. After around 1.5 hrs, the dough had risen. I punched the life out of it and made some naans.
AND they were good. I loved them. Ofcourse whole wheat naans taste different than the all purpose flour ones, but they are healthier.