router wont let me access internet after bridging modem, but a valid coection is visible

I bridged my ZyXEL modem because a colleague told me that their was NAT problems between my Asus router and modem. I personally don't know what exactly that means. But, I went ahead and bridged my modem, a program called inSSIDer showed me a valid coection, and so did my network and sharing center on my computer. However, it said "coected, no inteet access". Help, I dont know what to do. My ISP told me that the router has some setting telling it to not forward the coection to computers. How do I properly configure my router with a bridged modem.