I have just completed configuring a broadband connection to Plus.Net using an eTec Ethernet/USB ADSL Modem and a US Robotics 8054 Wireless + Ethernet router.
I wanted the wireless router as one of the computers is in another room in a different part of the house and this one had a good write up as working at 20 metres range. I set that up first and had the network running.
I then bought the modem. I couldn't find the US Robotics model with the Ethernet port so bought a different make.
I have had a lot of difficulty and tried a lot of options to get it all working. The main problem is that the instructions with the modem did not explain how to connect via a router, in particular not explaining how to configure NAT.