Mouse trail

**First Question:**How do you make the font color white or any other color?

Text = "Kirupa has the best site on the net!!!";
letters = Text.split("");
letterformat = new TextFormat();
letterformat.font = "Verdana";
letterformat.align = "center";
letterformat.size = "10";
spacing = 8;
speed = 3;
for (var LTR = 0; LTR<letters.length; LTR++) {
		mc = _root.createEmptyMovieClip(LTR+"l", LTR);
		mc.createTextField(letters[LTR]+"t", LTR, LTR*spacing, 10, 20, 20);
		with (mc[letters[LTR]+"t"]) {
				text = letters[LTR];
				selectable = false;
		if (LTR) {
				mc.prevClip = _root[(LTR-1)+"l"];
				mc.onEnterFrame = function() {
						this._x += (this.prevClip._x-this._x+5)/speed;
						this._y += (this.prevClip._y-this._y)/speed;
		} else {
				mc.onEnterFrame = function() {
						this._x += (_root._xmouse-this._x+10)/speed;
						this._y += (_root._ymouse-this._y)/speed;

**Second question: **
Okay, I made a complex button and it links to a certain place. How do I make it that when I click the button, it changes only a certain portion of the page to that place?

For example:

I have the title bar, then I have a black bar (navigation bar) and then I have a blue box undernear the navigation bar. Now I click a button on the navi bar and then the blue box changes to that location not the whole page. The title bar and navigation bar are still the same.