To download photos to a computer, you really should only need a USB cable, a computer with a USB slot, and your camera.
You cannot use just any USB cable to download your photos. Most point and shoot cameras use mini-USB connectors, and only certain USB cables will contain the correct connector for your camera.
Your camera manufacturer should have included the correct USB cable in your camera's box. If you cannot find the correct cable, you may need to take your camera to an electronics store or an office supply store and purchase a cable that has the correct size USB connector.