Okay, so obviously in the Wizarding World people need to keep their food cold, just like in our world. I've always envisioned them using some sort of charmed box, but I can't for the life of me think of how it'd be done, or what they'd call them.
And on the topic: what about toasters? or ovens, for that matter? How would wizards compensate for not having electriciy in this case?
Maybe the simply use the same appliances as muggles (Oven, toaster, etc.) but they're powered by magic. Or the same thing that powers the lightbulbs
Also apparently a use for Dragons' blood is to clean ovens. They must simply use ovens then. Surely if it was something different, it wouldn't of been given the same name.
I like the idea of wood-burning stoves a lot - I think they'd run on magical fire of some sort, though, not wood. I think that makes sense... And now that I think about it, I do remember reading that Mrs Weasley cooks on a stove-top so that makes sense.
Also, now that I think about it some more, I can remember on school camp we used these little cage-like things to cook toast over the fire. Mine always burned, but I think it's one of those things you just have to get the hang of. I can imagine wizards using something like that. Or maybe just doing what I do when our toaster breaks, and cooking the bread in a non-stick frypan.
The fridge thing, though, really has my mind confused. I read in one of those lovely other threads that were provided (and helpful, by the way) that maybe you could just leave the stuff outside 'cause it's colder. I should probably have mentioned that my particular fic's set in Australia, where it's never cold (except, apparently, for tonight). I do remember learning about these crazy Australian early fridge-like inventions the name of which I can't remember, and I wonder if that would work? Would wizards maybe use magically-enhanced old-fashioned fridges?
Kill the Spare
I envisage that they use something like an Aga, ( wood burning stove) to cook food. After all, they can light the wood easily enough and keep it burning, plus it would be easy to clean if you were a witch.
Regarding fridges, I read a fic once where they used a 'Chill Charm' to keep a cupboard cool. That would work well as a fridge. Of course, before Muggles had electricity, they had pantries which kept food cool, and generally bought their food fresher, or preserved it by salting or pickling it. Perhaps Wizards do that.
I think this topic is more suitable for the Reference Desk, where you'll find similar threads on the matter.
There's a thread here on Wizard Appliances
And one on Food here, which I think would be useful as they discuss where Wizards get their food. There's some mention about vegetable gardens and such, so maybe a lot of Wizards just grow their own food, and the Weasleys have their own chickens and such. Having that fresh food right there would eliminate the need for a fridge altogether.
I find these in the Filing Cabinet of the Reference Desk under Miscellaneous if you wanted to go check it out for youself!
In regards to what Carole said about having pantries that kept things cool, I'm pretty sure that pre-electicity, Muggles used underground areas called ice houses that would be filled with ice during the winter and some form of insulation to store their perishable foods throughout the year.
However, I'm not sure how much ice there is in Australia during the winter, so this idea may not actually be feasible.