One thing you can do is open a command prompt and run ipconfig /all. That will list your ip address DNS info etc. Clip and past that info here if you like and I'll have a look at it. When you don't have internet access can you access the routers status page, assuming you know how to do that. run ipconfig /? for a complete list of options.
I cannot copy and paste it as I am on my netbook, but is there any specifics your looking for?
Microsoft Windows [Version 6.1.7600]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.
C:\Users\Nick>ipconfig /all
Windows IP Configuration
Host Name . . . . . . . . . . . . : Nick-PC
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : 208.67.222.222
Wireless LAN adapter Wireless Network Connection:
Connection-specific DNS Suffix . : 208.67.222.222
Description . . . . . . . . . . . : Airlink101 MIMO XR PCI Adapter
Physical Address. . . . . . . . . : 00-14-A5-DB-84-D6
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::f4fe:f19:5b36:310b%12(Preferred)
IPv4 Address. . . . . . . . . . . : 192.168.0.145(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : June-25-11 11:35:39 PM
Lease Expires . . . . . . . . . . : July-02-11 11:35:38 PM
Default Gateway . . . . . . . . . : 192.168.0.1
DHCP Server . . . . . . . . . . . : 192.168.0.1
DHCPv6 IAID . . . . . . . . . . . : 301995173
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-14-F1-8C-87-00-23-54-89-B1-BA
DNS Servers . . . . . . . . . . . : 192.168.0.1
NetBIOS over Tcpip. . . . . . . . : Enabled
Tunnel adapter isatap.{637E3668-372C-45CD-BAB2-5C24B6EC01F8}:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Tunnel adapter Local Area Connection* 9:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Tunnel adapter isatap.phub.net.cable.rogers.com:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Tunnel adapter isatap.{7F5D3AE2-1822-42BD-89CD-A597FD50250A}:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #3
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Tunnel adapter 6TO4 Adapter:
Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft 6to4 Adapter
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Nevermind I finally got onto my desktop it allowed me to get on the internet, I deleted a few programs, maybe they were the reason, I now know maybe it was Hamachi that was causing the issue not sure but let me know what you see!