How can i connect my HDTV to my computer?

My HDTV is about 30 days new, (made in 2008). It's a Philips 42" 1080p flat screen. I want to know what cable would I need to display my computer's input on my HDTV. I have one cable already, but the output shows up extremely fuzzy, and even if i tinker with resolutions the picture doesn't get much better.

The back of my TV has every port imaginable (including several HDMI), but the connectors on my video card are limited to the blue socket (the one from my regular pc monitor to my tower) and a white connector (for a projector or something?) There is also a PS/2 port on the card, which i am using now to display the screen on my TV (the picture is horrible, as i've said before)

If anyone can provide me with product links, i would be very grateful.
***Correction (the cable i currently own is an S-Video)

The cable you want is a DVI-to-HDMI cable. The white connector I believe you are talking about is a DVI connector. DVI cables are normally used for cpu to monitor connections to process a digital signal. It is a long rectangular shape with a bunch of pin connections on one side and a single flat connection on the other (when looking straight at the rectangle shape). Go to firefold.com and you can buy one for about $15, including shipping.

S-Video can only process standard definition (480i), and it is not good at all as you have discovered. DVI cables (and HDMI) can process 1080p. I own a DVI-to-HDMI cable I use for connecting my cable box to my computer monitor to use as a second TV.