Menu bar problem

I am editing a template. I am not expert in making menu bar. I inserted a drop down menu under "Generator" menu which you can see here. http://www.aroundpublic.com/spew2
but you can see that it is still and not showing correctly. I want that when we move mouse on generator menu then its child menu should appear. also it is before jqueery slider images. please help me out . i am posting here css coding of menu bar.

/* menu */
.menu_nav { margin:0; padding:0 0 18px; float:left; width:auto; height:56px;}
.menu_nav ul { list-style:none; padding:0 0 0 2px; height:56px; float:left; background:url(images/menu_sep.png) no-repeat left top;}
.menu_nav ul li { margin:0; padding:0 2px 0 0; float:left; background:url(images/menu_sep.png) no-repeat right top;}
.menu_nav ul li a { display:block; margin:0; padding:0 0 0 20px; font-size:16px; line-height:20px; font-weight:bold; color:#fff; text-decoration:none;  text-align:center;}
.menu_nav ul li a span { position:auto;display:block; padding:20px 20px 18px 0; height:20px;}
.menu_nav ul li.active a, .menu_nav ul li a:hover {background:url(images/menu_a.png) repeat-x left top;}
.menu_nav ul li.active a span, .menu_nav ul li a:hover span {}

Code (markup):

Please help me out please.

 

see www.aroundpublic.com/spew i searched a lot last night and I found it.

 

I can make it for you. PM me.

 

It is done now.