Hey!i prefer tuna in water, usually for the breakfast, eggs, beans,green peas, chicken in different ways- boiled, grilled, in salad,in soup, eating buckwheat instead of rice. A lot of easy things what you can prepare very fast and healthy. Also we eat brown bread,sometimes full grain pasta, mushrooms cooked with vegetables. The main goal is to watch calories in and out.
There are a lot of things you can cook that are delicious, low calorie and good for you. Now is the time to teach your children good eating habits, as well.
Have you ever looked into stir fries? Veggies, lean meat, mushrooms, etc all put together and sauteed...
Make veggies (roasted, steamed, grilled) the center of your meals, then be sure to add a lean protein, in the form of lean meats, chicken, fish, low fat dairy, etc.
And speaking of salads -- there are a ton of those, aside from the traditional garden salad. Or have your garden salad and add grilled chicken, lean steak, etc to it.
Make sure you have protein with every meal or snack and drink lots of water.
Before you start anything, though, I highly recommend that you see your doctor and ask for some simple blood tests to rule out hypothyroidism and insulin resistance, since both cause weight gain/inability to lose.