You can chew on a couple of grains to see how they taste, but generally crushed grain is only good for a few weeks before it starts to stale. I wouldn't count on it. Dry yeast is almost certainly fine. I'd use it, but have an extra pack on hand in case. Hops would be best if they were frozen, but they'll be ok as long as they maintained their seal. Not in peak condition, but I've used worse. I wouldn't use them for a really hop-forward IPA, but maybe decent as a 30-minute addition and should be just fine as a 60 minute addition. But yeah, it's probably good you got them for free. The wild critters will love the grain, though!