[DemonOuterverse]

There's a conflict with your #header style. With the float:left, it's causing the table with the flash to float to the left of the header DIV.

If you change it from:

#header {
    clear: both; 
    float: left; 
    margin: 10px 5px; 
    width: 450px;
}

To:

#header {
    clear: both; 
    margin: 10px 5px; 
    width: 450px;
}

Another option would be to move the flash into the header div, but that would then cause the forum tables to float to the left of the header and the flash.

---
On an unrelated note, I noticed that the header text's background is the same as the page's body background.

I'd look at also changing:

<table style="border: 1px solid #666666;" width="760" cellpadding="0" cellspacing="0" border="0" align="center">

to:

<table style="border: 1px solid #666666; background:#FFFFFF;" width="760" cellpadding="0" cellspacing="0" border="0" align="center">

so that the header matches the rest of the forum's background instead of the body background color.

---
And one final thing, the header text doesn't match the way it looks on the rest of forceunleased.org.
I'd change:

#header h1 a {
    
    text-decoration:none;    
    border:none;
}

to:

#header h1 a {
    font-family:"Times New Roman", Times, serif;
    color:#000099;
    text-decoration:none;    
    border:none;
}

because it seems that it's inheriting vBulletin's link style there. I'm not sure what the exact color is, but #000099 came very close.

One last thing. Eliminate the <center></center> thing if you're going for XHTML 1.X compliance.