I wouldn't worry about those temps too much as it won't affect your performance, but for piece of mind, the Zalman VF900 might lower them a little. Of course you might void your warranty on the card so be wary.
For the harddrive itself cooling isn't important, a harddrive's pefromance isn't degraded by the heat it generates. But depending on the way your case is setup, some heat from the drives may affect other components, or ambient case temp. Particularly if you have 3 or more harddrives, or a small...