If you mean to change the wording, it's in the Database, under the "Vocabulary" tab, and then under the "Terms 5" tab. The wording is on the right side.

If you mean the title graphic, it's under the "System" tab. Hit the "Set" beside the current title graphic. Don't forget, to use custom graphics, you have to import them, using the "RAW Material Editor", or stick 'em in your RTP folder.