How do I strengthen my wireless internet signal?

I have Comcast Internet and in order to network my house we bought a Netgear Wireless N router, one of the best on the market according to many professionals and computer magazines. We figured this would provide us with the strength needed to network our house but it didn't So we got a second one of these Netgear Wireless N routers to act as a repeater. Unfortunately, between the main router and my room (about 65 -70 feet away), the internet signal seems to get lost. I still have my local signal at full or almost full strength but no internet signal and when I do I only have tops 2 mbps when my wired connection tops out at 20 mbps. My friend whose tech savvy said that's no where near Wireless N speeds or even Wireless G speeds (my computer only picks up on the G signal). So I want to know if there's anyway to prevent the internet signal from getting lost in translation here. The routers have internal antennas, which point in all directions and like I said, I have a problem with the internet signal, my local signal is fine.