What could be wrong with my internet connection? (Router trouble?)

A couple days ago, my Mac Mini starting experiencing random internet lag. Basically, it will work fine for 5 to 10 minutes, and then for 5 to 10 minutes, pages just won’t load. I can actually connect to the page, but nothing will pop up. I’ll just get a blank page with “waiting for facebook.com” at the bottom. I went through the regular procedures, unplug the modem, unplug the router,restart the computer, etc.

Now here’s where it gets weird. My laptop running Windows 7 isn’t experiencing any problems at all. I can browse the internet for hours on it without any issues. This led me to think that my Mac was the problem, EXCEPT now my XBox 360 has the same problem is well. Which pretty much throws online gaming and Netflix streaming out the window. Even odder, while the Mac and laptop are connected over WiFi, the XBox is connected to the router through an ethernet cable.

Any ideas as to what the problem is? The modem and router are only a month old, so I don’t think the hardware could be failing already. The router is password protected, and no one else is accessing it. The router is a Netgear WGR614 Router.