Not when MAME is running in full screen mode. You would need to run MAME in Windowed mode and use software to remove it's titlebar and borders and position it so it fills the screen. An AutoHotkey script could do it.
Eg.
WinSet, Style, -0xC00000; remove the titlebar and border(s)
WinMove, , , 0, 0, 640, 480; move the window to 0, 0 and reize it to 640x480