Don't remember seeing a VGA adapter for the PS2. What you could do is feed the video through something like a TV tuner card or digital video card, something that has a video input and displays the video feed on your monitor. I had a cheapo USB TV Tuner I was using to play PS2 on my monitor. Picture was blurry and the colors were suck but that's because it was a USB TV tuner. Get a PCI one, streams faster and better quality.
Viper GTS -
That's some pretty cool stuff! Never seen one of those before, how's the quality on those?