Your video card has a monitor connection, a yellow female RCA plug, and an S-video connection on it? If so, I would guess that the RCA plug is for video in, while the S-video is for video out.
If you want to play DVDs from your computer to your TV, you'll need to connect the S-video connection to your TV. If your TV does not have S-video In, then you'll need to buy an adapter or a special cable.
You could check the manual to see if it tells you what each port on the video card does.
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AMD Athlon XP 2500+ 1.83GHz @ 2.09GHz 1.65v (167*12.5)
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2 x Samsung DDR SDRAM 256MB PC2700
Seagate Barracuda IV 80GB 7200rpm ATA-100
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LiteOn Black DVD-rom 16x
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Windows XP Professional
Creative Inspire 5200 5.1 Black Speakers
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