Robert is entirely right.
I might add, however, that Ziplock bags didn't work for me, two of them ended up bursting (only in the "zip" part) in the car, I had to hold them together, water splashing on me during the ride. This may not be the case with you, but I highly suggest specimen bags. They're cheap (and free every now and then) at many
LFS. Double bagging is a must.
Make sure to leave plenty of air in the containers, especially if you aren't using a pump.
I also reccomend "Cycle". It comes in a little white bottle, and "cycles" your water. This doesn't at all mean you shouldn't keep the substrate, old water, and filter bacteria intact, but it can help with any fresh water you add to the tank, and cuts down on stress. There is another type of similar thing, Bio-Spira, but this is apparently harder to get. I haven't tried it, myself, but it comes highly suggested from other, more experienced tank-owners.
Good luck with your move!