O.o I thought, you need help with an HTML Template :p
For the Fix, you'll need to find someone who is good in CSS & XML
For fixing it you'll have to edit the XML for the skin.
May be, you'll have to pay someone or you can download an eBook on CSS & XML and learn it within a month and then fix this skin lol
Seriously, ask anyone good in XML
EDIT:
I got an answer, its due to some Module which you have installed on your forum.
Please make another DEMO forum on the same domain and install the skin there
and see if the problem is in the skin or due to the modules
Hope this solves your problem