I don't think you can totally turn off logging, but you can temporarily set the recovery model to simple via:
ALTER DATABASE yourdatabase
SET RECOVERY SIMPLE
which will minimize the amount of log space used.
Make sure you have a full backup before you make your changes, as the only recovery possible using the SIMPLE model is to restore from the last backup.
Also make sure to set it back to whatever model your database is currently using.
Custom Apps, Inc.