I keep it in the pantry until it's opened. Once I use it for the first time, I put it in the fridge. It really doesn't make any sense when you think about it. The ketchup bottle is left on the table at restaurants. I guess I put it there because my parents did the same when I was younger.
As for brands, I buy
Red Gold which is made right here in Indiana. I refuse to buy Heinz because of a certain whore associated with the brand...