AT&T Adsl with cisco 3620 or 1750

I have a static ip account (ADSL) and would like to use my either my 1750 or 3620 to route inside my house. I do have one ADSL wic, on the 1750 I have one FA and on the 3620 I have 2 Ethernet ports. Can some one provide some me with some help on this one. WHat are the commands I need to use in order to get this to work?

Thanks