I used to live on frozen food and still have about one meal a day that way.  You can spend a lot of money on some of them.  I mostly stuck with Swanson and Banquet, and did not mind eating the same one over and over again.  Now, it's mostly Banquet pepperoni pizza, fish sticks, and chicken finger meals.  I don't know why, after all these years, Banquet still attempts to have mashed potatos in some of their meals.  Apparently other people keep buying it.  The Banquet roast beef is like eating shingles.  The brownie in the chicken finger meal is excellent.  If I ran Banquet, I'd market entire trays of that frozen brownie.  All of these are three minutes in my microwave, and the only thing I have to wash is a fork.

Some of the microwavable soups were good.  They usually only took about a minute and a half in the microwave.

Otherwise, I used to buy frozen pizzas, break them in smaller pieces so they would fit into the microwave, and zap them until the cheese melted.

Instant oatmeal is not bad in the microwave either.

These days, my wife makes one fantastic meal almost every day.  Sometimes there are leftovers.  No one eats better than I do these days.:)

-Just wanted to add that if you are going to live like that for an extended period, you might want to buy a bottle of multivitamins and take one every day.