besides what CTM said, this is only a personal thing, but I don't like seeing Windows XP folders at every board I go to. You can look around the UBBDEV db or request something in the Graphics forum that would be more in tunes with your specific board.
Also, anyone who doesn't notice the mislignment on the main forum it's cause at 1280x1024 maximized, it looks normal. Also, a reordering of your forums might help the flow. Announcements forums should be at the top if you want them read, and private forums should be at the bottom cause most people when they visit don't wanna have to scroll cause they aren't allowed in any of the first forums.
One more thing, it might just be my resolution, but have you considered setting the default text size to a little larger, ie 2 for main, 1 for small.
Also, on your statistics page, you might want to fix the part where you have 2 $show_logouts, and the bug (not your fault) where there is a weird table around pages.
Just a couple thoughts though
), the only thing I would say that is off-putting is the mis-alignment of the separated categories in the forum summary. Check that the widths of the table cells match up with each other. Also, maybe make "Topic Starter" match up with "Last Post" on the forum pages (like, have the date in bold at the top, then the user name underneath)? But I'm scraping the bottom of the barrel here. 
I love the colors you've chosen and how you divided it up. Nice usage on the icons. The text is small but on a 1024x768 is readible. I'm about the DJ scene (turntablism)...Great stuff. 
