Quote Originally Posted by Freedie
but my computer have never get infected by virus yet so we dont need to get a router.
(Maybe I have not yet get the punishment for not using a router)
You can afford a computer. You can afford high speed access. Your router might cost 1/3 of what my first one cost. But you don't want to spend the money for safe access.

It doesn't sound like the router is your only problem anyway, since as far as I know your modem is only USB. You couldn't hook a router up to a junky usb-only modem even if you had one. But if the modem maker does not provide Linux drivers then there is nothing that I can do to help you. There isn't much more that I can tell you that I have not already covered in the above links.