[solved]Widths in IE, Opera and FF

I'm helping a friend with his webpage.
As usual it's the differences in different browsers that's the hardest part about it.
This is what it looks like:
http://w1.481.telia.com/~u48111784/operaff.jpg
The way it looks in IE/Opera is the way I want it. How do I make it look like that in FF as well?

Code:

---

<div class="s_text">
        <div class="bigPicture">
                <img src="art/room_m.jpg" width="320" height="240" alt="Click this image to get a bigger one">
        </div>
        <div class="infoText">
                <p>This image is really nice</p>
        </div>
        <div class="imgnav">
                <a href="JavaScript:slideshowBack()"><img src="site_images/button_arrow_left.jpg" alt="Previous image" class="arrow" /></a>               
                <div class="navthumbs">
                        <img src="art/room_s.bmp" width="50" height="38"
                        /><img src="art/ocean_s.jpg" width="50" height="38"
                        /><img src="art/earth_s.jpg" width="50" height="38"
                        /><img src="art/chair_s.jpg" width="50" height="38"
                        /><img src="art/car_s.jpg" width="50" height="38"
                        /><img src="art/boxx_s.jpg" width="50" height="38" />
                </div>
                <a href="JavaScript:slideshowUp()"><img src="site_images/button_arrow_right.jpg" alt="Next image" class="arrow" /></a>
        </div>
</div>

---

Code:

---

img {
        border: 0;
        padding: 0;
        margin: 0;
}

img.arrow {
        float: left;
        margin-top: 6px;
}

div.bigPicture {
        font-size: 0;
}

div.bigPicture, div.infoText {
        position: relative;
        left: 50%;
        width: 335px;
        border: 3px solid blue;
        padding: 4px;
        margin: 10px 0 10px -168px;
}

div.imgnav {
        position: relative;
        left: 50%;
        margin: 0 0 10px -199px;
        width: 398px;       
        padding: 0;
        font-size: 0;
}

.imgnav img {
        margin-right: 4px;
}

div.navthumbs {
        float: left;
        border: 3px solid blue;
        padding: 4px 0 4px 4px;
        width: 334px;
        height: 38px;
        margin: 0;
}

---

So what about the margins/padding of s_text and the elements surrounding it?

Code:

---

div.s_text {
        font-family: verdana;
        font-size: 11px;
        color: #FFFFFF;
        text-align: left;
}

body {
        background-image: url(site_images/back_lines.jpg);
        background-repeat: repeat;
        background-attachment: fixed;
}

td {
        font-family: verdana;
        font-size: 11px;
        color: #FFFFFF;
}

---

There are no rules for tr or table.
Yeah, yeah, I know. Shouldn't use tables. But it's not my page, I'm just helping a friend with the art gallery.

I solved it, my DOCTYPE was messed up