GNU Emacs 23.2.1を使い始めたのですが、新しいフレームを作成（C-x 5 *）すると、背景色・文字色等の設定が上手く読み込まれません。

それらの関数では現在のフレームに適用されるだけで、新しいフレームには適用されないからでしょう。default-frame-alist か custom-set-faces で設定すると良いと思います。

以下、M-x customize で生成した custom-set-faces の例です。

(custom-set-variables
  ;; custom-set-variables was added by Custom.
  ;; If you edit it by hand, you could mess it up, so be careful.
  ;; Your init file should contain only one such instance.
  ;; If there is more than one, they won't work right.
 )
(custom-set-faces
  ;; custom-set-faces was added by Custom.
  ;; If you edit it by hand, you could mess it up, so be careful.
  ;; Your init file should contain only one such instance.
  ;; If there is more than one, they won't work right.
 '(default ((t (:background "#202020" :foreground "#cccccc"))))
 '(cursor ((t (:foreground "#999999"))))
 '(font-lock-builtin-face ((((class color) (min-colors 88) (background dark)) (:foreground "#ffffff"))))
 '(font-lock-comment-face ((((class color) (min-colors 88) (background dark)) (:foreground "#99cccc"))))
 '(font-lock-constant-face ((((class color) (min-colors 88) (background dark)) (:foreground "#cccc99"))))
 '(font-lock-function-name-face ((((class color) (min-colors 88) (background dark)) (:foreground "#ffffff" :weight bold))))
 '(font-lock-keyword-face ((((class color) (min-colors 88) (background dark)) (:foreground "#9999cc"))))
 '(font-lock-string-face ((((class color) (min-colors 88) (background dark)) (:foreground "#99cc99"))))
 '(font-lock-type-face ((((class color) (min-colors 88) (background dark)) (:foreground "#cccc99"))))
 '(font-lock-variable-name-face ((((class color) (min-colors 88) (background dark)) (:foreground "#cc9999"))))
 '(font-lock-warning-face ((((class color) (min-colors 88) (background dark)) (:foreground "#cc3333"))))
 '(region ((((class color) (min-colors 88) (background dark)) (:background "#999999")))))