Interesting ... I also use a gigabyte wireless router (which one do you have?), and AFAIK the default IP for the Gigabyte is 192.168.1.1 (check on the 1st or second page of the manual).
You best bet is to start the configuration over, as then you will know exactly which IP is which. Pop a paperclip into the reset button on the Gigabyte, it will restore factory settings (just make sure you copied all your settings for reconfig). You should then connect your pc/notebook via one of the Ethernet ports to the Gigabyte (just make sure you are on the same net eg. 192.168.1.x.) I am running mine on 192.168.2.xxx, and assigning IP's to my devices using the Gigabyte's DHCP server.
Keep in mind, I am using iBurst, and not ADSL, so I might be talking bollocks wrt the link between the ADSL router and the wireless router, but to me it sounds like there is a bit of an IP mix-up