Internet connection problem HELP!!

I seem to be having a problem on a desktop. Windows XP. Apperently I can go on the internet using the browser OPERA but I can not use any other browser or Instant Messaging software. Everytime I open a browser, it desplays a message saying that it can't connect to the server hosting the website.

Here is my output for ipconfig /all (I erased anything containing my name)

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

Windows IP Configuration

Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : hsd1.ca.comcast.net.

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : hsd1.ca.comcast.net.
Description . . . . . . . . . . . : Intel(R) PRO/100 VE Network Connecti
on
Physical Address. . . . . . . . . : 00-12-3F-A7-BB-EB
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.1.100
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1
DNS Servers . . . . . . . . . . . : 68.87.76.178
68.87.78.130
68.87.69.146
Lease Obtained. . . . . . . . . . : Tuesday, May 19, 2009 8:14:01 PM
Lease Expires . . . . . . . . . . : Wednesday, May 20, 2009 8:14:01 PM