Where I live I currently don't have a toaster, baking sheet, pan, or really anything that I could use as a container in the oven.
I'm starving and I'd like to heat up some frozen waffles and was thinking about just laying them down between the edges like in this picture:
http://upload.wikimedia.org/wikipedia/commons/b/ba/Oven.agr.jpg
Is this safe/okay to do? I don't really know anything about cooking.
Not only is it okay to do so, I frequently place waffles directly on oven racks after making them fresh to keep warm or to cool before freezing (without ruining the crisp crust, as happens when you put them on a plate or stack them).
There's no reason you can't heat items you'd normally put in a toaster (or toaster oven) in a normal oven. The only possible problem is having to clean up any mess that results (in this case likely only crumbs) after the oven has cooled.
Just make sure the racks/grill are clean, and watch the temperature and time so they don't burn.
It's okay to do so. There are mini-ovens / toasters where you put pop-tarts/ toast/bread/waffles directly on the (clean) grill.
Nick Johnson, source
If the heating rods are directly in the base (like in orinary big eletric ovens) make sure that no crumbs are on the base. This can cause nasty burnt crumbs. Or at least remove the crumbs after you heated up your waffles.
