Parent Child width problem in IE

This is a site im working on for a friend

http://www.floodstock.com/overland

this is a temporary location for the site until I finish it. The issue is with the main menu. The only dropdown I have right now is for the "tour" button, child menus. The issue is that in IE7 the parent, tours, is taking the width settings of the child menu items..Ive tried to modify the css to fix this and move the width setting around. Nothing seems to be helping...here is the css from the custom css file I made.

Thank you :)

Global CSS for ALL menu types
******************************/

ul.nice-menu,
ul.nice-menu ul {
list-style: none;
padding: 0;
margin: 0;
}
/*MAIN MENU*/
ul.nice-menu li {
border-top: 0;
float: left;
background:none;

}

ul.nice-menu a {
}

ul.nice-menu ul,
#header-region ul.nice-menu ul {
top: 2.9em;
margin-right: 0;
}

ul.nice-menu ul li {
}

******************************/
HORIZONTAL (down) menus
******************************/

ul.nice-menu-down {
float: left;
border: 0;
}

ul.nice-menu-down li {
}

ul.nice-menu-down li li {
border-top: 0;

}

ul.nice-menu-down ul {
left: 0;

}

ul.nice-menu-down ul li {
clear: both;
background:url("./images/blocktitlebar.jpg");
border: 1px solid #000;
width:10em;
}

ul.nice-menu-down .menuparent a {
}

/* mousover DOWN */
ul.nice-menu-down li.menuparent,
#header-region ul.nice-menu-down li.menuparent {
}
/* mousover MAIN */
ul.nice-menu-down li.menuparent:hover,
ul.nice-menu-down li.over,
#header-region ul.nice-menu-down li.menuparent:hover,
#header-region ul.nice-menu-down li.over {
}

ul.nice-menu-down li li.menuparent,
#header-region ul.nice-menu-down li li.menuparent {
}

ul.nice-menu-down li li.menuparent:hover,
ul.nice-menu-down li li.over,
#header-region ul.nice-menu-down li li.menuparent:hover,
#header-region ul.nice-menu-down li li.over {
}