TW Services completed its acquisition of Denny's Inc. for $218 million . . . Robert Half International Inc. has acquired the Robert Half and Accountemps franchises in New York and Cincinnati for $15.7 million in cash and notes . . . Treasury Secretary James A. Baker III said finance ministers from the seven major industrial nations will meet in Washington this month to discuss economic policy coordination . . . Standard & Poor's said it has placed Asarco Inc.'s double-B rated senior debt on its CreditWatch surveillance list with positive implications.