How to install /configure GD library for PHP 5 on appache / windows xp ?

The default windows distribution of PHP comes with GD. So enabling the GD extension should be as simple as opening your php.ini file and uncommenting the necessary line. So this line:

Code:
;extension=php_gd2.dll
Should look like this (Remove the preceeding semi-colon):

Code:
extension=php_gd2.dll
Generally, your php.ini file will be in the folder in which you installed PHP.