Toolbar -> Config button -> Interface tab -> Bottom check-box: "On-Screen Display Messages"
To remove FPS (not on by default), go to Toolbar -> Graphics -> Other (bottom section) -> "Show FPS" (top left checkbox)
To remove lag counter (not on by default), go to Menubar -> Emulation -> "Show Lag Counter"
To remove FPS (not on by default), go to Toolbar -> Graphics -> Other (bottom section) -> "Show FPS" (top left checkbox)
To remove lag counter (not on by default), go to Menubar -> Emulation -> "Show Lag Counter"