I made a tote for a friend from FL to take pizzas back. She has the local pizza pub make the pizzas and freeze them for travel. I used insulbrite to line the bag (placed with the insulbrite side facing the inside of the bag to reflect heat/cold).

I found raincloth fabric at Joann's. It's thin, but waterproof and reasonably priced. You can't put pins in the raincloth, other than in the seam margins, but it worked well and can be washed quickly with a quick swipe of a cloth. Of course, laminated or oilcloth is good too, as Karen mentioned.