The service menu's switches are available in the core Options (in the RGUI) for FBAlpha, but for some reason they don't seem to apply.
Mame2003-plus starts the game directly in English, so there was no need to enter the service menu - accessible by pressing Tab and entering the MAME menu. I think for Mame2003-plus the MAME Tab menu it's not enabled by default (as @Riverstorm said) and you need to enable it in the core Options from the RGUI.
