Good news, you sure can. Qwest by default is a ppp connection, depending on if you are static or dynamic IP, install the NIC as usual, (your distro should support the 3com) setup your hostname, hosts, etc. A difinitive guide can be found at
Randy Lutton's Homepage select linux config. This has a detailed setup page, you wont have to do anything with your router as it has its own OS (cBOS), you should not have to change a thing. The routers address by default is 10.0.0.1, you will need a hub if you plan on adding your other systems to the connection. Though Qwest does not support this, it can be done, fairly easily.
give that page a look-see and let us know how it went.