I froze some steaks and now they are gray around the edges. Does that mean they're bad?"
What you're describing is "freezer burn", which sounds a lot more ominous than it is. Freezer burn, which is caused when that cold freezer air comes in contact with the food surface, won't make you sick. But eating freezer-burned meat is like chewing leather--it's dry and flavorless and a real workout for your jaw. Cut the "burned", or grayish-brown dry spots‚ away before cooking.
To help prevent freezer burn, wrap meat and poultry so the entire surface comes in direct contact with the plastic wrap. This may entail wrapping individual steaks separately, rather than as one big package. Get the plastic wrap as close the the food surface as you can, and double wrap when possible. Then place the wrapped items in a freezer-proof plastic bag, removing as much air from the bag as possible before sealing. Don't forget to mark the bag with the name of the food, the weight or amount, and the date you put it in the freezer.