This is basic stuff kids, but for those who are interested in displaying an image instead of the title of your site where "PunBB.org Forums" is located in these forums.
All you need to do is go into the file header.php and change the line.
$tpl_main = str_replace('<pun_title>', pun_htmlspecialchars($pun_config['o_board_title']), $tpl_main);
(I recommend you dont actually change it, just comment it using // before it)
to
$tpl_main = str_replace('<pun_title>', '<img src=http://yoursite.com/image.gif>', $tpl_main);
Simple as pie, hope this helps.
Edit: Found a few bigggg bugs, gotta figure it out, if anyone knows how to fix the ones that I KNOW they KNOW are there!, please let me know :) thanks... I am going to have this fixed within the hour.
Edit Again: Okay I found the problem, it actually wasnt a problem with my idea, my idea works fine...I just kinda tried to edit the actual Title using admin options, to see if it would accept the html, but it doesnt...so dont bother trying. Just one of those things...you test and test to realize you made a silly mistake -_-, man am I embarressed.