Yup you have the correct cables Lancelot.
On my notebook, in order to push the video out to the s-video port you have to press the function + F4, i presume this is what you have to do on most pc's. AFAIK, you don't need to change the display settings unless you want to run the tv as an additional monitor to the original screen.
So on your pc, its probably the function key and one of the F keys, look for one that looks like a monitor or something like that. Your notebook screen should flicker and either show exactly whats on the tv or it will be blank, and you will only be able to see the tv.