Flash Drive if
you only want to transfer your files. It is the easiest and, since it can be used over and over, probably the least expensive in the long run.
Buy the largest one you can afford, plug it into your old computer's USB port and simply click-and-drag files to the flash drive. It only copies them, so you aren't in much danger of deleting them from your old computer. Then plug the Flash Drive into your new computer's USB port and click-and-drag the files into whatever folder ("My Documents", "My Photos", etc.) you desire. It may not be as fast as the cable method, but it is easier and safer and the files can be deleted from the flash drive as soon as you are ready to use it to load the next batch. Just remember to delete the files from your flash drive as soon as you are done using it, since anyone can pick up that drive, put it in their pocket and have whatever information you put on it. Also, I'm no expert, but I understand that what is deleted from a flash drive cannot be recovered, so it is safe once it is deleted.