All of these dishes can be reheated simply in a microwave. Here are some things that might be an improvement if you want to take the time:
Dolmeh / Cabbage Rolls: These are in a sturdy foil and can go (still wrapped) on a baking sheet into an oven at 350-degrees until warmed through (about 15 - 20 minutes . . . you can just put these in and walk away, they're pretty sturdy). I've cooked these less-long than traditional Eastern European cabbage rolls because fresher seems more Persian to me. There is no culinary evidence to back that statement up.
Sumac Lamb: The problem with reheating the lamb in the microwave is that it would be easy to overheat, and also there is a crunchy rice crust in there that's supposed to stay crunchy. It's called tahdig. So cooking this up in a skillet with some oil may be better.
Potatoes & Spinach: I did not cook these in butter because I wanted to keep them vegan, however sauteeing in butter would taste great.