Mass browser error.

Hey, here is screenshots of my website in different browsers:
http://browsershots.org/http://www.wifeee.com/V2/

What I dont get is that they all go the right!
My site is:
http://wifeee.com/V2/index.php (ps, the online now counter is experiencing hyper-activity)
and in my Broswer (Firefox 2.0, Windows VIsta Home Premium, Sony Vaio NR - VGN-NR11Z)

Any help appreciated.

It's a good practice to check the validity of the document before checking the cross browser behavior. see http://validator.w3.org/check?uri=http%3A%2F%2Fwifeee.com%2FV2%2Findex.php&charset=%28detect+automatically%29&doctype=Inline&group=0

Try this change in your CSS stylesheet file:

html, body {
margin:0px auto;
width:800px;
text-align:center;
background-image: url(back.jpg);
background-repeat: repeat-x;
font-family: verdana;
}