With cooler weather here, my family always has some stew in the freezer that can just be heated up and served with cornbread.
To make our stew, we go the easy route. I buy canned veggies and stew meat. I brown the stew meat in a skillet. Then in a large pot or crock pot I add the stew meat and all the veggies (with the juice). We generally use: Large can of crushed tomatoes, large can Ranch Style Beans, corn, sliced carrots, green beans, peas, diced potatoes, peas, any vegetable you like. Put all the veggies and meat in a pot and heat it up until it boils lightly, then simmer for some really good stew. If you do this on the weekend, then you can cool it down and freeze it for any other day for dinner. I use those Ziplick Containers with the twist on lid. Then the day I'm going to serve it I make some fresh cornbread, which can be made earlier in the day before your 3 year old has his cranky time, and reheat that when dinner is ready.
We also get meatloaf ready ahead of time and just put it in the oven the day we are going to eat it. This can be done a couple days in advance and kept in the fridge, but any longer than that I freeze it. For our meatloaf we use Stove Top stuffing and BarBQ Sauce instead of bread crumbs and ketchup. I bake it for about an hour, depending on the size of pan, on 375. Then I make instant mashed potatoes and frozen corn to go with it - both really easy to do.
Another way to save time for dinner prep is to cook chicken on the grill over the weekend and heat it up with some veggies or a salad for dinner. You can load up that grill with chicken, steaks, hamburger patties on the weekend and either freeze or refrigerate the food until you are ready to use it.
As for crock pot ideas, we love a pot roast in the crock pot. I buy an arm roast. First thing in the morning I put in a bag of baby carrots, then the pot roast, I pour Lipton Onion Soup on the pot roast, and I add new potatoes cut into pieces. I add just enough water to cover the carrots. Cook on low all day, I usually turn it to high about an hour before serving.
Check out this blog http://crockpot365.blogspot.com. This lady has a crockpot recipe posted for everyday in 2008, we have tried the Hashbrown Casserole and are going to try Shepherd's pie. We have a bunch on our list to try, she has some really interesting ideas and gives you her family's feedback on each meal.
When in doubt, my family LOVE Stoffer's meals and casseroles. Just throw that in the oven, serve with a salad, or my kids love carrot sticks, tomatoes & broccoli with ranch.
Another suggestion, get your older two to help out with dinner. I know that sounds like more work, but involving the 3 year old may actually distract him from this "cranky" time.
Good luck and congrats on the new baby!