Try removing the quotes from around the php4apache.dll path. If that doesn't work, there should be a directory called /modules in the Apache root folder (ie. d:\local\apache\modules). Copy the php4apache.dll file into that folder and change the LoadModule statement to:
&bnsp;LoadModule php4_module modules/php4apache.dll
Also, make sure you've copied the php4ts.dll file into c:\winnt\system32 and php.ini to c:\winnt. Restart Apache, it should be working now.
For whatever reason, specifying a path outside of the Apache root works on some installations, but not on others. In my experience, calling the mod from the /modules directory always works.
-geoff