Hmmm I don't think the one you can remove is there any longer in the default. I think you'll have to wait to hear from BbBoy about that but I think that banner on your board is only removeable with upgrading to a paying version of Best Board service...From our pricing page here
The FREE plan
This plan is 100% FREE
Popups and ad banners will be displayed on your board.
Includes all features except for File Hosting, BbRemote, and Full Log. These features take up bandwidth which does not get paid for by the adverts. If you want these features, then it's only $2.50 (2 American dollars and 50 cents) per month - see below.
The Fixed Plan
This plan is a flat fee of $2.50 (US$) per month.
Up to 2 popups per IP# per 12 hours will occur.
There are no banner adverts.
Full access to all services and features is given, except BbRemote.
The Variable Plan
There is no popup or banner advertising whatsoever.
Full access to all services and features is given.
The cost varies depending on the amount of bandwidth you use - $6 per GB (1024mb), the minimum charge being $2.50 per month. Tip - Even very popular boards don't usually use up more than 1GB of bandwidth per month.