OS X :: Internet Connection Difficulty With Both Ethernet Cable And AirPort?

I connect to the internet mainly through an ethernet cable, connected to my own base for ethernet connections (Might be a router, but doesn't connect directly to the internet) which is connected to the main Linksys router on the other side of my house, which even has a wireless connection.

Regardless, this setup has worked without issue for a long time now, but all of a sudden now, I cannot connect to the internet (On my Mac).

I have tried unplugging the routers, for extended periods of time, plugging them back in, but I cannot connect to the internet. Whats awkward, is that when I check the Network settings in the System Preferences, it says clearly is that the Ethernet Cable is connected (Which it is), and as a backup, I have even connected to my Wireless Network through AirPort (Which says it is connected), but I cannot connect to the internet through Firefox, or any instant messaging service.

On the main computer, with the main router, the internet works fine. When I try to load Firefox on my Mac, it sometimes takes a long time loading (On a blank screen), and never loads usually (With occasional loads, but usually does not connect).