null -ing stuff Help

if I have:

Actionscript Code:

public class Gate extends MovieClip {
         
        
            private var sC1 = new SoundChannel;
        private var dO = new Sound(new URLRequest("open.mp3"));
        private var dC = new Sound(new URLRequest("close.mp3"));
        private var night = new Sound(new URLRequest("night.mp3"));
        private var gateContainer:* = new MovieClip();
        private var DoorL:* = new doorL();
        private var GtGlow:* = new gtGlow();
        private var ent:*= new invisB();
        private var blr:* = new BlurFilter(5,5,1);
        private var glo:* = new GlowFilter(0xE5DADA,1,10,10,3,3,false);
        private var DoorRbmd:BitmapData = new doorR(0,0);
        private var GateFrbmd:BitmapData = new gateFr(0,0);
        private var DoorR:Bitmap = new Bitmap(DoorRbmd);
        private var GateFr:Bitmap = new Bitmap(GateFrbmd);
        private var ceoFen:* = new Sprite();
        private var Fen:*= new fen();
        private var fenCast:* = new castL();
        private var sta:* = new staklo();
        private var GlowF:* = new glowF();
        private var arrayMc:Array;

//.. rest of the class

and after Im done with this class (Gate), and click to another(Page1), can I do:

Actionscript Code:

arrayMc = ceoFen = DoorR = DoorL = Fen = fenCast = 
                ent = GateFr = GtGlow = GateFrbmd = GlowF = sta = 
                gateContainer = blr = glo = dO = dC = night = null;

I mean it works I guess, profiler doesnt show them lingering around in Page1, but is this the right way to remove stuff and save memory ?

That's technically valid albeit a bit sloppy.
You cannot manually remove items from memory, only the garbage collector can do that. Nullifying merely makes things eligible for garbage collection. The key GC eligibility is removing all references. Nullifying the parent class instance removes it as the only reference to its properties (in most cases) thus eliminating the need to clear each property individually. You of course have to stop all playing movie clips, remove any listeners, shut down all streams any other logical activity before nullifying the parent. Having a public function called destroy() is common practice.

myParentClass.destroy();
myParentClass = null;

Newer versions of the flash player are better at doing a lot of this along with letting you trigger the garbage collector on command but until you're familiar with how that works, this is a good practice.