Can you please tell me how to fix whats wrong?

<script language="JavaScript"><!--

browserName = navigator.appName;

browserVer = parseInt ( navigator.appVersion );



version = "n2";

if ( browserName == "Netscape" && browserVer >= 3 ) version = "n3";

if ( browserName == "Microsoft Internet Explorer" && browserVer >=4 ) version = "e4";



if ( version == "n3" || version == "e4" )

{



about_on = new Image ( 134, 94 );

about_on.src = "menuimages/about_on.gif";

products_on = new Image ( 72, 69 );

products_on.src = "menuimages/products_on.gif";

news_on = new Image ( 134, 70 );

news_on.src = "menuimages/news_on.gif";

links_on = new Image ( 134, 94 );

links_on.src = "menuimages/links_on.gif";

guestbook_on = new Image ( 134, 94 );

guestbook_on.src = "menuimages/guestbook_on.gif";

email_on = new Image ( 134, 70);

email_on.src = "menuimages/email_on.gif";





about_off = new Image ( 134, 94 );

about_off.src = "menuimages/about_off.gif";

products_off = new Image ( 134, 108 );

products_off.src = "menuimages/products_off.gif";

news_off = new Image ( 134, 70 );

news_off.src = "menuimages/news_off.gif";

links_off = new Image ( 134, 94 );

links_off.src = "menuimages/links_off.gif";


guestbook_off = new Image ( 134, 108 );

guestbook_off.src = "menuimages/guestbook_off.gif";

email_off = new Image ( 134, 70 );

email_off.src = "menuimages/email_off.gif";






}



function button_on ( imgName )

{

if ( version == "n3" || version == "e4" )

{

butOn = eval ( imgName + "_on.src" );

document [imgName].src = butOn;

}

}



function button_off ( imgName )

{

if ( version == "n3" || version == "e4" )

{

butOff = eval ( imgName + "_off.src" );

document [imgName].src = butOff;

}

}

// --></script>

I would also like help removing all the old code that is no longer needed.

Thanks so much for all your help

I would also like help removing all the old code that is no longer needed.

probably all of it given that it seems to be covering for very old versions of NS & IE

What are you trying to achieve and what is it not doing ?

I don't know really. It was a pre made layout that I have been editing.

I think it has something to do with the mouse over effect you get with my images.

That is the only thing out of the ordinary that my page does.

Thanks so much for helpng me out