"I have a wireless router which I reset "
Surely you will have to set the router up again,as there is no ip address assigned.
If this is the case,make sure you delete all evidence of the previous setup to reduce any conflicts.
Ive been having my own router problems recently and found reseting the router and like above deleting all traces of any previous setup and running regscrubxp click here to rid the obsolete registry entries.Now everything works ok.
One more thing...you have fitted the filter to the phone line ?