Hi, actually @graykevinb may have missed a step here.
First, I would double check that you put the SD Card in before powering up the GoPiGo. If you reverse this process, you can corrupt the SD Card. It sounds like you've reburned the SD card, and we're past that.
Your PC should be connected to the same wifi network that your Pi is connected to. Just wanted to check that this is correct in your case?
Also, I wanted to check: you're using Raspbian for Robots (did the SD Card say "Raspbian for Robots" on it?).
Now that the ethernet port is lighting up, your Pi has a connection to the network. If you have bonjour installed and you are still unable to connect by typing in "http://dex.local" in the browser, and you're not able to ping dex.local on the command line of your PC, I recommend that you use the Fing App (instructions here on how to use) to find the IP address of your Raspberry Pi on the network.
The fact that you have one single LED on the ethernet connection is fine, just as long as we're seeing some lights on the ethernet port.
Once you make the connection and can see the Raspbian for Robots page, you should be able to click right into noVNC.
Also, I'm assuming you have the GoPiGo2; here is a page with more information on getting setup and connected.