Delay between animations

How do i put delays in my script i get the following error...

Script error: Update() can not be a coroutine.

I am very noob so be nice, I want it like this.

function Update () {

if (Input.GetButtonDown ("Fire3"))

animation.Stop("Run");

animation.Stop("Walk");

GetComponent(Fast).enabled = false;

animation.Play("Skid");

yield WaitForSeconds (5);

GetComponent(Slow).enabled = true;

Fast and Slow are both Third Person Controllers

This is just an example But lets say i wanted to switch from a character movement with no item in hand animation set to animation with item in hand animation set.

So in simple terms Player Stops moving, Animation Fast Script is disabled, Animates Skid Yield gives time for the animation to skid then the second set of animations begin

Take a look at these pages:

http://unity3d.com/support/documentation/ScriptReference/index.Coroutines_26_Yield.html

http://unity3d.com/support/documentation/ScriptReference/WaitForSeconds.html

Basically what it says is that Yield WaitForSeconds can only be used inside a function started as a Coroutine.