Most people upload a 1024x768 image, but you've got it configured to scroll after about 300px. It should be set to 768px before scrolling. I know phpBB has the setting in there somewhere...
For a sample check out this thread: http://starportgame.com/sgeforum/viewto ... start=1024
Uploaded images are great (no more photobucket!) but its almost unusable when every image scrolls.
phpBB Forum setting: uploaded image height dimension
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