No, the cable that stbr51 uses with the 500 MHz iBook will not work with the 700 MHz model.
You need the Apple Video Adapter:
http://store.apple.com/us/product/M9109G/A
Is that the one they sold you? If so, you also need a composite (RCA) video or s-video cable. All the adapter does is give you the ports you need to plug the cable into.
Since the Apple Video Adapter is video only, you also need an audio Y cable to get the audio from the headphone port and to the TV (or VCR > TV). The TV (or VCR) must be equipped with the ports (including the audio-in port) necessary to get this done.