Well, after I quick look, I guess the problem lies here..
if(isset($_POST['submit'])){
$banpath = "../banners";
copy($our_file, "$banpath/$our_file_name") or die("Couldn't Upload the file!");
$query2="INSERT INTO banners (memberid, categoryid, sizeid, name, url, weighting, filetype, approved) values ('$membername','$categoryg','$pc_id','$name','$url
','$weight','$our_file_type','Y')";
mysql_query($query2) or die( "ERROR: " . mysql_error() . "\n");
} else {
die("Something went wrong hmmmmm........");
}
Surely, when the page first loads, the variable $_POST['submit'] hasnt set yet. So, it will always gives u die("Something went wrong hmmmmm........");.