SELECT B.FILEID, B.WORD, TF.T_FREQ
FROM TF INNER JOIN INFOGAIN200 B
ON B.WORD=TF.WORD
ORDER BY TF.T_FREQ DESC;
Anyways FYI, you cannot use ORDER BY clause inside derived tables. You will get error
The ORDER BY clause is invalid in views, inline functions, derived tables, subqueries, and common table expressions, unless TOP or FOR XML is also specified.