Can anyone explain how "meals on wheels" works? The different options, etc.

There's nothing to it, usually you just fill out an application. They deliver home cooked meals, Mon-Fri, except for holidays. Where I live, in Alaska, they only deliver Lunch. The people doing the deliveries are all volunteers, and they are the nicest people. They visit with Mom everyday, and I noticed the difference in Mom (having company of her own, even if it's just for 10 minutes)!