pg probably already helped you out a lot, but I'd like to point your direction to HTML::Template too (there are even Tutorials about this: HTML::Template Tutorial and Using HTML::Template). I have started working on HTML::Template a couple of days back, and must say, it's a breeze for these kind of things.

Another thing I find perculiar about your code, is that you don't use CGI's capabilities much. For example, you could rewrite this:

print "<input type=hidden name= 'index'  value='$i'>";
print "<input type=hidden name='uname' value='$nme'>";
print "<input type='image' src='http://typhoon.he.net/~bthcraft/$nme/i
+mages/tn_$dat->[$i]->[2]' name='image' height ='$heigh$
[download]

To:

print hidden("index",$i), 
       hidden("uname", $nme),
       image_button(-name   => "image", 
                    -src    => "http://typhoon.he.net/~bthcraft/$nme/i
+mages/tn_$dat->[$i]->[2]",
                    -height => $height,
                    -width  => $width);
[download]

IMO, this makes it easier to read and it's less chars to type :)