I always put my hops in the freezer. Even if it's for a few days. I have space in there, and it's the best choice, so why not? The oils in hops are somewhat ephemeral, so I do what I can to preserve them.
Specialty grains I don't worry as much about, although I mill my own grains. If I knew I wasn't going to use them for a while, like a couple of months, and they were already milled, I'd probably put them in the freezer then, or at least vacuum seal them.