Need help-confused on top margin space with div in sidebar div

Question

Hello,
I have tried for hours to figure out what is affecting the margin of the top right div #first_ad which is contained in #sidebar2. Right now I have that div first nav with 10px top that looks like 30 in IE7 and 40px in iIE8 (chrome, firefox are fine). I have tried 0 margin on p and h tags and other things to lord only knows what else. I just cannot see what is affecting this.
If I could understand this it would be of great help as I seem to run into this alot with placing a div in a sidebar. I start out by using the dreamweaver templates in cs4 as my base.
Here is the link to the page.
http://www.hanovertypocraft.ca/test2/index3.html
Thank you for any assistance you may give me!!
below is the css
@charset "UTF-8";
body  {
margin: 0; /* it's good practice to zero the margin and padding of the body element to account for differing browser defaults */
padding: 0;
text-align: center; /* this centers the container in IE 5* browsers. The text is then set to the left aligned default in the #container selector */
color: #FFF;
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: 100%;
background-color: #000;
background-image: url(../images/hantypbg2.jpg);
background-repeat: no-repeat;
.thrColFixHdr #container {
width: 900px;
text-align: left; /* this overrides the text-align: center on the body element. */
margin-top: 50px;
margin-right: auto;
margin-bottom: 0;
margin-left: auto;
background-image: url(../images/container_bkgd.png);
background-repeat: no-repeat;
.thrColFixHdr #header {
padding: 0;
height: 110px;
margin: 0px;
clear: none;
float: left;
width: 740px;
.thrColFixHdr #header h1 {
margin: 0; /* zeroing the margin of the last element in the #header div will avoid margin collapse - an unexplainable space between divs. If the div has a border around it, this is not necessary as that also avoids the margin collapse */
padding: 10px 0; /* using padding instead of margin will allow you to keep the element away from the edges of the div */
.thrColFixHdr #sidebar1 {
float: left; /* since this element is floated, a width must be given */
width: 165px; /* padding keeps the content of the div away from the edges */
display: inline;
.thrColFixHdr #container #sidebar1 p {
margin: 0px;
padding: 0px;
#header #head_logo_text {
height: 110px;
width: 355px;
margin-top: 0px;
margin-bottom: 0px;
margin-left: 225px;
color: #FFF;
font-size: 18px;
font-family: Arial, Helvetica, sans-serif;
font-weight: normal;
clear: none;
float: left;
margin-right: 0px;
padding: 0px;
#header #head_logo_text a {
color: #FFF;
#header #head_logo_text p {
font-family: Arial, Helvetica, sans-serif;
font-size: 16px;
line-height: 21px;
margin: 0px;
padding: 0px;
.thrColFixHdr #container #header img {
margin: 0px;
padding: 0px;
#nav_home {
width: 135px;
padding: 0px;
margin-right: 15px;
margin-bottom: 0px;
margin-left: 15px;
height: 320px;
margin-top: 10px;
.thrColFixHdr #sidebar2 {
float: right; /* since this element is floated, a width must be given */
width: 140px; /* padding keeps the content of the div away from the edges */
margin-right: 10px;
padding: 0px;
margin-top: 0px;
margin-bottom: 0px;
margin-left: 0px;
background-color: #00F;
.thrColFixHdr #container #sidebar2 h1 {
margin: 0px;
padding: 0px;
.thrColFixHdr #container #sidebar2 p img {
margin: 0px;
padding: 0px;
.thrColFixHdr #container #sidebar2 p {
margin: 0px;
padding: 0px;
#mainContent {
margin-top: 10px;
margin-right: 160px;
margin-bottom: 0;
margin-left: 175px;
padding-top: 0;
padding-right: 10px;
padding-bottom: 0;
padding-left: 10px;
#mainContent p {
font-family: Arial, Helvetica, sans-serif;
text-align: center;
font-weight: normal;
font-size: 16px;
line-height: 20px;
margin: 0px;
padding: 0px;
#mainContent #flash_div {
width: 353px;
margin-right: auto;
margin-left: auto;
border: 3px solid #000;
height: 265px;
overflow: hidden;
.fltrt { /* this class can be used to float an element right in your page. The floated element must precede the element it should be next to on the page. */
float: right;
margin-left: 8px;
.fltlft { /* this class can be used to float an element left in your page */
float: left;
margin-right: 8px;
.clearfloat { /* this class should be placed on a div or break element and should be the final element before the close of a container that should fully contain a float */
clear:both;
    height:0;
    font-size: 1px;
    line-height: 0px;
#sidebar2 #first_ad {
height: 140px;
margin-top: 10px;
margin-bottom: 10px;
border: 1px solid #000;
#sidebar2 #second_ad {
height: 140px;
margin-top: 10px;
margin-bottom: 10px;
border: 1px solid #000;
#sidebar2 #third_ad {
height: 140px;
margin-top: 10px;
margin-bottom: 10px;
border: 1px solid #000;
#sidebar2 #fourth_ad {
height: 140px;
margin-top: 10px;
margin-bottom: 10px;
border: 1px solid #000;

Answer 1

Thank you.
I am relatively new at this and you guided me to google the patch and how to overrice it using - padding 10px !important; on my css which let me override the  fixes padding.
I was under the misconception that the IE fix being in grey was only for information not actually pertinent.
Again thanks and I will try to research more regarding the implimentation of these patches