Approach on changing row color on orders grid in a

I need to change row color in magento orders grid based on order status. For start I don't want a complex solution with configurable interface. I just want to know where to start.

What is the best approach ?

Full, working solution:

Copy js/mage/adminhtml/grid.js to js/colors/adminhtml/grid.js

Make the file 666 and the folders (js/colors & js/colors/adminhtml) 777.

Edit it and after line 208 (before the line containing }.bind(this)) add:

colorize();

At the end of the file add:

function colorize () {
    $$('td').each(function(macguffin) {
       if(macguffin.innerHTML.strip()=="Processing") macguffin.parentNode.setStyle({backgroundColor: 'Orange' });
        if(macguffin.innerHTML.strip()=="Pending") macguffin.parentNode.setStyle({backgroundColor: 'Gold', color:'Black' });
        if(macguffin.innerHTML.strip()=="Payment Review") macguffin.parentNode.setStyle({backgroundColor: 'LightPink' });
        if((macguffin.innerHTML.strip()=="On Hold")||(macguffin.innerHTML.strip()=="Payment Review")) macguffin.parentNode.setStyle({backgroundColor: 'HotPink' });
        if(macguffin.innerHTML.strip()=="Suspected Fraud") macguffin.parentNode.setStyle({backgroundColor: 'Red' });
        if((macguffin.innerHTML.strip()=="Closed")||(macguffin.innerHTML.strip()=="Canceled")||(macguffin.innerHTML.strip()=="Cancelled")) macguffin.parentNode.setStyle({backgroundColor: 'LightBlue', fontStyle: 'italic' });
        if(macguffin.innerHTML.strip()=="Complete") macguffin.parentNode.setStyle({backgroundColor: 'Green' });
  });
}
document.observe("dom:loaded", colorize);

Now create or edit the admin local.xml file in app/design/adminhtml/default/default/layout/local.xml

Edit it to include:

<?xml version="1.0"?>
<layout version="0.1.0">
  <default>
    <reference name="head">
        <action method="removeItem"><type>js</type><name>mage/adminhtml/grid.js</name></action>
        <action method="addItem"><type>js</type><name>colors/adminhtml/grid.js</name></action> 
    </reference>
  </default>
</layout>

The orders grid will now be in vibrant colours and you should be able to clearly see what orders need attention.

The colorize() function can be edited to suit your order states and preferred colour scheme.