Menu following Mouse

Hello everybody!

menuMC.onEnterFrame = function() {
	var yMouse = _root._ymouse;
	if (Math.abs(yMouse-this._y)<1) {
		this._y != 100;
	} else {
		this._y -= (this._y-yMouse)/10;

I made this small code but now I have the problem that the menu is following the mouse everywhere in my small movieclip on the _y axle.

How can I rewrite the code so tha moveclip is inside an area.

Please, But I don’t want to use drag and drop.