BAP,
YOU CAN use the switch.
The same cable you had plugged into your router you simply plug into your switch on the WAN port.
Then, you can plug the cables going to your computers into any empty port on the switch.
SHould work fine.
With a router you get firewall protection and it will issue a new IP address. THE SWITCH WON'T, but it will allow you to have your computers accessing the internet.
No reason why you can't ue it and get it up and running.
Heck, I had a switch plugged into the modem over at my old plant and had five computers running. No biggie.
Use the switch.
micro...