Hooking PC to JVC LCD Television?

I have a 37" JVC LCD mounted on my wall, I have ran 1 HDMI, 1 Coax, and 1 Set component cables to this TV. The cables run into the back of a closet where I have a Wii, DVD player, HD dish receiver, Surround Sound Head, and a VCR. The dvd player is tied onto the coax via a converter plugged up in series with the VCR. The HDMI is ran directly between the Sat. Receiver and the TV. The component cables run to the Wii. I use a Universal RF-10 remote package to control all of it. What I would like to do is hook an old computer up as well. I have a lot of home movies stored on my computer, I also have 3 towers sitting around going to waste. None of the computers have Video Cards with compatible outputs to the TV. Can I use an adapter to convert the VGA signal to a Component cable? What would be drawbacks? What are advantages? and what would this cost minus the cost of additional component cables?