Connect to Internet (ISDN line) via router

Hi!
I use Suse 8.2.
I am unable to connect to the net from the Linux system. I have the following set up. Linuxsystem --> Hub --> Router --> Modem --> internet.
I used Yast2 --> Network Basic --> Network Card Configuration --> Already configured devices --> Change --> Ethernet etho --> Edit --> Network address setup --> Static address setup 192.168.2.3 (local Lan) and Subnet mask 255.255.255.0. In Host name and server name --> Hostname Linuxsystem and Domain name mylan.com. In Routing configuration --> Default gateway xxx.xxx.x.x provided by the ISP. What am I missing out? Where do I give the DNS? In Name Server | Domain Search? If so, how? Like 1. xxx.xxx.x.x | myisp.net and 2. xxx.xxx.xx.x | myisp.net?
I am currently using the Linux system as Samba server and am able to mount other systems like Win98 and in turn be accessible from Win98 via Samba login.
Do I need another NIC/Ethernet card?
Thanks in advance.

You will probably want to give it the IP of your router as the default gateway, not your ISP's gateway.

Thanks!
But I am a newbie. :( How do I find out my router's IP?

Well, that I cannot tell you. You are the one who configured that router, right?

Say, not to get off topic, but I'm using another type of ISP. Broadband(Comcast). I'm using the same thing he is. I'm using the router to get connected. All I needed was to know what exactly is the Host name and Domain name and how to obtain it. I know I sound dumb by asking, but can you please help me out? thanks.