Are you possibly thinking about having the game paused but the menu is still animate? If so its easy..To set the screen to 0 use.
System-set time scale to 0
and to keep your menu going at regular speed
System-set object time scale
choose object and set to 1.0
wait for signal "start"
keyboard-on key is down
system-signal "start"
set "menu" invisible
not too sure what you want but just mess around with the time scales and signals.