sqlserver 2000 with navision 3.70 linked server

Hi, I have a sql server 2000 database with a linked server to navision 3.70 with its own database. Now I see all the navision tables in enterprise manager. My question: how could I make a new query on tables from sqlserver and tables from the linked navision server? (for examle a join) what is the difference between when I import that navision 3.70 table over odbc to sqlserver and make than a query on that table and an other sqlserver table again the first case? How can I make a linked server navision 3.70 (with its own database) in sql server 2005? Thanks