Crackers
Yes, I have a grandmother who does this. She stores her dry crackers in the fridge and swears that it preserves them… I’m not so convinced. When trying to keep crackers tasty (and not stale) keep them in a tightly sealed bag in the pantry or any other dark place in your kitchen.
Yogurt
I can hear the debaters coming out of the woodwork for this one. Yogurt is made from milk, but it is filled with bacteria (the good ones, relax). If the yogurt is unopened then you can safely keep it out of the refrigerator in a cool place out of the sun. If you want to eat it, perhaps pop it into the fridge so that it is cooler for your pleasure.