The easiest, most fool proof "first smoke" is pork butt. At it's best, it will be falling off the bone, as it should, and be flavorful with a wonderful smoke ring. At something less, generally if you have not left it in the smoker long enough, it will still be fully cooked, just will not be falling off the bone. Still taste good.
And chickens, esp whole chickens, can be rather easy, and much quicker than a 7-8 pound pork butt. Chops go quickly, too. Ribs aren't really hard, just a little more than the butt.
The only thing I've been disappointed in, and might not try again, is duck. But the goose came out great! And when the goose fat caught fire, we had some great live entertainment, too!
Don't use too much wood for the smoke flavor. With too much smoke, the meat becomes bitter.
Since there's usually just the two of us, I've learned that smoked items freeze well for later consumption.