Controlling the loader component with action script

I am having troubles on doing some action script in Flash Mx 2004.

I am building a website; on the first frame it has the preloader component and a loader. The movie that the content path is set to, currently loads fine for the homepage. when I click on a button, I want it to change the contentPath of the loader, and then redo the preloader (so it loads the new movie).
I also want it to unload the existing movie.

What action script would I use to accomplish this, mine is not working.

Thanx in advance,
3dnirvana

Great! This is just what I needed! Thank you very much!