2. If you mean a one-piece garment, I would call it a snow suit.
3. Rain suit
4. We call them shovels.
5. Yes, sandbox.
6. There are many different kinds of hats and different words to describe them: hat, cap, tam, fedora, stetson, cowboy hat, toque, stocking cap, baseball cap, Panama hat, boater, bonnet, bowler, chapeau, skimmer, sombrero, stove pipe hat, straw hat, ten-gallon hat, top hat, beret, bonnet