Well, if you have the asus v7100t you should have both s-video and composite out, since my tv has both there´s no difference except it´s easier to use the composite one.
If you have a scart connector on the back on your tv, buy an adapter for s-video and/or pal to scart, it´s cheap and will get the job done. And yes, all u need is a gfx card with tv-out to be able to enjoy emus and other things on your telly.
Using the tv as a monitor shouldn´t be recomended, unless you have a really good tv, i.e hdtv, otherwise the text will become hard to read. The card I´m using has a crontel chip but with more expensie solutions you could probaly get a better picture because of the higher resolutions allowed. If your tv has a low dot pitch number, 0.22-0.25 you will get an awesome picture.