HELP: Tables on the same line, problems

I am creating tables inside a big table, and am having problems with the actual height, the big table for some reason is twice the height I want it to be, and it means that I have to scroll down the page to get the tables, is this a frequent problem when putting tables inside a big table to make them appear on the same line? How can I make sure that the big table fits correctly over the tables inside it?

It would help a lot if you could post a link to the page in question, or at least post the markup in here (not preferred, but if you do please use the "code" bb-tag; it's under the hash mark at the top of the message box); your description doesn't provide nearly enough information to say anything helpful about this.