So, if I understand your question, your internet works well when you connect it directly to your computer, but when you try to connect it to your Linksys the wifi is not working properly?
Ok - a few more questions:
1 - If it's new and unconfigured, it probably broadcasts a wifi signal as "linksys" - what wifi networks CAN you see?
2 - When the router is on and connected, which lights are lit and which ones are flickering?
That sounds right for the model. What is the wifi network name you are used to seeing when it is working?
That's a great name.
Have you always seen the "Century9411" network also? I'm asking because I'm wondering if your router didn't reset itself to a factory configuration.
Do you have enough cables to connect your computer to a port on the back of the router and leave the internet line plugged into the router at the same time?