from this you can see if your PC's DHCP client is enabled, and what IP address your PC has.
your IP address should read 192.168.X.XXX if you have a generic Router and the DHCP is functioning correctly. if it says 169.254.1.XXX then the DHCP client could not acquire an address from your router.
usually single PC internet problems are caused by something at that PC, either with the cable or the Network card/driver/settings. use the same IPconfig Command on another PC on the network and see if that pc settings are different from the non connecting PC.
you can try an uninstall/reinstall of your network drivers from the control panel to reset the driver and the settings.