The 15pin port on a laptop is a VGA port, that will not let you run the signal through a TV unless you have a modern flatscreen TV with a matching VGA port on it, then you just need a standard PC monitor lead. (and a 3.5mm jack to 2 phonos for the audio)
if your laptop had a tv out it will probably be a small round port like this (possibly yellow in colour)
http://www.sprut.de/misc/video/tv/svhs.jpg
If you have one of these you can connect your laptop to any TV with a scart socket using suitable leads, be aware that this is a low quality video connection though and not suitable for day to day use, only for video and maybe games.