You should post the code as everyone doesn't have that theme.

Please see coding below. I would like to either completely remove it or add in coding to have drop down boxes where required

/*
Big Business Theme for Concrete5 by iLP -http://www.concrete5.org/profile/-/view/82852/...
Based on an Original Design by Free CSS Templates -http://www.freecsstemplates.org...
Released for free under a Creative Commons Attribution 3.0 License
Name : Big Business Theme for concrete5
Description: A two-column, fixed-width design with clean, professional look and a bright color scheme.
Version : 0.9.8
Released : 20120923
*/
* {
margin: 0;
padding: 0;
}

body {
background-image: url(img/cedar.gif);
background-repeat: no-repeat;
background-size: cover;
}

br.clearfix {
clear: both;
}

.box {
overflow: hidden;
margin-bottom: 1em;
}

#banner {
margin: 0 0 0 0;
height: 250px;
position: relative;
padding: 20px 20px 1px 20px;
width: 950px;
}

#banner .pic {
padding: 9px;
}

#c5wrapper {
position: relative;
width: 980px;
margin: 75px auto 0 auto;
background: #FFFFFF;
}

#c5wrapper h1,h2,h3,h4 {
font-weight: normal;
letter-spacing: -1px;
}

#c5wrapper h2 {
font-size: 2.25em;
}

#c5wrapper h2,h3,h4 {
color: #2C2B2B;
margin-bottom: 1em;
}

#c5wrapper h3 {
font-size: 1.75em;
}

#c5wrapper h4 {
font-size: 1.5em;
}

.ccm-search-block-submit {
margin-left: 1em;
color: #FFFFFF;
padding: 10px;
background: #2FACAC;
border: 0;
}

.ccm-search-block-text {
border: solid 1px #8F8F8F;
padding: 10px;
}

#content {
width: 665px;
float: left;
padding: 0;
}

#content-full {
width: 890px;
padding: 0;
}

#content-leftsidebar {
width: 665px;
float: right;
padding: 0;
}

#content-box1 {
width: 320px;
float: left;
}

#content-full-box1 {
width: 437px;
float: left;
}

#content-box2 {
margin: 0 0 0 345px;
width: 320px;
}

#content-full-box2 {
margin: 0 0 0 452px;
width: 437px;
}

#footer {
clear: both;
margin: 40px 0 120px 0;
text-align: center;
color: #8C8B8B;
}

#footer a {
color: #8C8B8B;
}

#header {
height: 172px;
position: relative;
background: #D2D3D5 url(img/Header6.gif) top left no-repeat;
padding:
color: #D2D3D5;
width: 978px;
border: solid 1px #D2D3D5;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
overflow: hidden;
}

img.alignleft {
margin: 5px 20px 20px 0;
float: left;
}

img.aligntop {
margin: 5px 0 20px 0;
}

img.pic {
padding: 5px;
border: solid 1px #D4D4D4;
}

#logo {
line-height: 160px;
height: 160px;
padding: 5px 0 0 0;
position: absolute;
top: 0;
left: 45px;
}

#logo a {
text-decoration: none;
color: #FFFFFF;
text-shadow: 0 1px 1px #3E3E3E;
}

#logo .title {
font-size: 3.25em;
}

#page .section-list {
list-style: none;
padding-left: 0;
}

#page .section-list li {
clear: both;
padding: 30px 0 30px 0;
}

#subtitle {
line-height: 160px;
height: 160px;
padding: 5px 0 0 0;
position: absolute;
right: 45px;
top: 0;
}

#subtitle h2 {
color: #BEBEBE;
font-size: 1.25em;
text-shadow: 0 1px 1px #3E3E3E;
}

#menu {
padding: 0 45px 0 45px;
position: relative;
background: #209D9D url(img/img02.gif) repeat-x top left;
margin: 0 0 0 0;
height: 60px;
line-height: 60px;
width: 890px;
border-top: solid 1px #5AD7D7;
text-shadow: 0 1px 1px #007D7D;
}

#menu a {
text-decoration: none;
color: #FFFFFF;
font-size: 1.25em;
letter-spacing: -1px;

}

#menu ul {
list-style: none;
}

#menu ul li {
padding: 0 20px 0 20px;
display: inline;
}

#menu ul li.first {
padding-left: 0;
}

#page {
padding: 45px 45px 15px 45px;
position: relative;
width: 890px;
margin: 0;
}

#page .section-list {
list-style: none;
padding-left: 0;
}

#page .section-list li {
clear: both;
padding: 30px 0 30px 0;
}

#page ul {
list-style: none;
}

#page ul li {
border-top: solid 1px #D4D4D4;
padding: 15px 0 15px 0;
}

#page ul li.first {
padding-top: 0;
border-top: 0;
}

#page-bottom {
float: left;
clear: both;
margin: 0;
background: #6E6E6E url(img/img03.jpg) top left no-repeat;
border: solid 1px #7E7E7E;
width: 888px;
padding: 45px 45px 0 45px;
color: #DCDCDC;
border-bottom-left-radius: 5px;
border-bottom-right-radius: 5px;
}

#page-bottom a {
color: #F5F5F5;
}

#page-bottom h2, #page-bottom h3, #page-bottom h4 {
color: #FFFFFF;
}

#page-bottom ul {
list-style: none;
}

#page-bottom ul li {
border-top: solid 1px #8F8F8F;
padding: 15px 0 15px 0;
}

#page-bottom ul li.first {
padding-top: 0;
border-top: 0;
}

#page-bottom-content {
width: 665px;
float: left;
}

#page-bottom-content-leftsidebar {
width: 665px;
float: right;
}

#page-bottom-sidebar {
width: 200px;
margin: 0 0 0 690px;
}

#page-bottom-sidebar-left {
width: 200px;
margin: 0 690px 0 0;
}

#sidebar {
width: 200px;
padding: 0;
margin: 0 0 0 20px;
float: left;
}

#sidebar-left {
width: 200px;
padding: 0;
margin: 0 20px 0 0;
float: right;
}

Hi
You need to edit the code. Go to ROOT/packages/theme_big_business/themes/theme_big_business/elements/header.php and find the below code:
Then replace it with
Then save the page and login to site. After that edit any page and add amiant_css3_menu block. Then choose your preferred settings. It will display the drop down menu.

Edit: You can use Amiant CSS3 Menu (http://www.concrete5.org/marketplace/addons/amiant-css3-menu/). Its free of cost and have the dropdown features.

Thanks
got rid of that menu but now when i install a new one the drop down doesn't work no matter what i do

What you mean by install new one?

When I installed the new menu (acient or default one) it doesn't show the drop down even if all of the settings are correct

Is there any live link to look at?

Www.accommodationtamborine.com.au