Ok, so purusing the AS3 board it appears that most of the people who have started using AS3 actually generally know what they're doing. Mind if a relative newbie joins the conversation?

I am upgrading code from AS2 to AS3 because I need the imrovements made to the FileReference class in AS3. Upgrading everything is a fair bit of busy-work, but one simple thing is giving me trouble right now.
The lack of a _level0 or _root reference is tripping me up, since these have been removed in AS3. At times I want to be able to reference certain arrays by variables instead of simply coding the name of the array. For example, my AS2 code works with an array of arrays like this:
var masterArr:Array = new Array("apple", "banana", ... , "fruit");
var apple:Array = new Array(valueA, ... , valueI);
var banana:Array = new Array(valA, ... , valN);
...
var fruit:Array = new Array(valueX, ... , valueY);
... later ...
function loadImagesByName() {
for (var i = 0; i <= masterArr.length; i++) {
var imgNameToLoad:String = "";
var name1:String = masterArr[i];
for (var j = 0; j < _level0[name1].length; j++) {
/*Note: _level0[name1] refers to the "apple" through "fruit" arrays declared above*/
imgNameToLoad = name1 + _level0[name1][j];
/*go on to load the image, etc.*/
}
}
}
Without the _level0 reference, how do I access my "apple" through "fruit" arrays by variable names? Can I just use "[name1][j]" instead of "_level0[name1][j]"? In AS2 I can't do that... and I can't test right now 'cause there are a ton of other things I need to update in my code before it will compile in AS3.
Also, a separate question. Is
addChild(myChild); exactly the same as
this.addChild(myChild);? If not, what are the differences?
Thanks so much for your help.
wearHD