Good DSL connection, no Internet access

At long last, when DSL service became available in my neighborhood, I signed up with Verizon. After installing the modem (Westell WireSpeed) , filters, and an ethernet board on my Dimension 4500 running XP Home Edition, not only can I not get onto the Internet via DSL, I can't get on via my dial-up connection. My daughter is home from college with her Dimension 4600, and it connects just fine when hooked up to the same modem and phone line, so the service is obviously active. The lights on the modem are green. The LAN status shows to be enabled.

I've tried several things:

• multiple times I have unplugged the modem and turned off the computer, most recently for two hours based on a suggestion in this forum;
• I've done System Restore back to the 19th, the day before I installed the modem;
• suspecting a conflict with MacAfee, I have uninstalled VirusScan and Firewall; 
• I've talked to three different Verizon support people;
• the ipconfig command yields this information:

Ethernet adapter Local Area Connection 3:

Connection-specific DNS Suffix:

Autoconfiguration IP Address: 169.254.0.6

Subnet mask: 255.255.0.0

Default Gateway:

Can anyone help? This is so frustrating!