Your description is hard to picture. Can you throw a screenshot up (upload it here and not on a public photo sharing site because I, and others, can't access those while at work).
Are you using Access 2007 and have the curent database property "document windows option" set to Tabbed Documents? That forces the form to fill your screen. If so, select the overlapping windows option if you want it to look like it would in access 2003 or older.