To add to the above - I always cook meatloaf, slice it, & freeze the individual slices well-wrapped in plastic wrap & then placed in a freezer Ziplock bag. What's nice about this is that you can take out just as many slices as you need - enough for a dinner, or just one for a nice meatloaf sandwich. I thaw & reheat them in the microwave & they're good to go.
And of course, as others have advised, chilis, non-cream-based soups, stews, baked pasta dishes, etc., all freeze & thaw great!!