The best thing I ever did was to let go of the expectations that come with being a SAHM, yes I aim to have a happy baby a clean house and a good meal at dinner time but I don't let myself get frazzled anymore, the kids are more important and I find that DH is happier to come home to me having a giggle with DD and no dinner than getting through the door to a screaming child me cranky and a gourmet dinner. So what I'm saying is just relax do your thing with your kids and you'll see when you're happier and calmer things fall in place.
As for the food, there's loads of easy meals and freezer friendly recipes out there. I find bolognaise sauce is awesome for freezing you can make bulk and defrost as needed, you can use it on pasta, lasagna or add some beans an make nachos its even great on toast for a quick fix!
If you don't have a slow cooker think about investing in one (they're not expensive $50 should get you a decent one) they're great for casseroles, just throw in the ingredients and forget about it! It doesn't get easier than that.
personally I'm not a big fan of freezing pasta and rice... It just goes soggy and gross but I do make the sauces and freeze those.
Hope this gives you some ideas :-)