What is the correct way to write this conditional statement?

You need to add your function in the template_redirect hook. You need to first wait for wordpress to finish loading pages before you can add your hook to remove wpautop, otherwise your hook will simply get run over. So your funtion will look like this

function pietergoosen_remove_wpautop() {
if ( is_page ( 'services' ) ) {
remove_filter( 'the_content', 'wpautop' );
remove_filter( 'the_excerpt', 'wpautop' );
}
}

add_action( 'template_redirect', 'pietergoosen_remove_wpautop' );