Hi Lee
I don't know if this will help but here are a few suggestions anyways.
First, when you installed php you must have copied one of the files which was to be named php.ini, I had one such problem when I copied the php.ini-opt file and renamed it. Then i deleted that file and I copied the php.ini-dist file and renamed it. And swoosh! everything was working
Second did you install php as a cgi executable or as a binary file. Installing it as a cgi executable has some advantages, althogh there may be a slight decrease in speed, but then Windows is supposed to slow everything down isn't it?
Finally you mentinoed that your net too has stopped working. So it would suggest that you have got a problem with your dns settings. You can check it out by typing 216.239.33.100 instead of google and if you are successful then you have to do something abt the way dns is installed on ur machine.
And last but not the least if it does not work, blame M$ and format ur disk and start all over again ;-) (Kidding......)