Maybe this will help.
Here is the .emacs file created after adjust the default face background color:
(custom-set-variables
;; custom-set-variables was added by Custom -- don't edit or cut/paste it!
;; Your init file should contain only one such instance.
)
(custom-set-faces
;; custom-set-faces was added by Custom -- don't edit or cut/paste it!
;; Your init file should contain only one such instance.
'(default ((t (:stipple nil :background "#bfbfbf" :foreground "#000000" :inverse-video nil :box nil :strike-through nil
verline nil :underline nil :slant normal :weight normal :height 90 :width normal :family "adobe-courier")))))
Does this help?