Honestly, about all you can do is try it. I suspect the yeast is long since toast... it needs to be frozen for storage past 6 months or so. Fortunately, it's still under 5 bucks at Sam's Club for that size pack!
The cheese is likely to have darkened (not sure what you are talking about here, exactly... a "cheese food" product, dried cheese?) If it's a wet product, I doubt it's any good. This would be the one thing I'd be awfully careful "trying out"...
And the coffee... you're just going to have to try it... we've used 8 year old coffee in the old style tin cans (which yours probably are, not the dumb aluminum foiled cardboard or plastic they've got now), but it was stored in our basement, which runs around 60° peak temp, and around 50° much of the year. You'll be able to tell on the first cup if it's not up to par.
Summerthyme