Sandwiches can be thawed in the wrapper. A sandwich that's removed from the freezer in the morning is will not spoil by lunch time at room temperature. There are a few things to remember when preparing foods for the freezer. First, freezing does not sterilize foods. It does slow down the growth of bacteria that cause food spoilage but does not kill them.
Some foods require special preparation.
You don't want to blanch veggies too long. They'll begin to cook. Check a cookbook for times. Meats should not be frozen for more than a few weeks in the store wrapping. You'll want to repackage using butcher paper, heavy duty aluminum foil or freezer wrap.