The best option is to select to 'Auto Delete the oldest recordings' when disk space remaining on your hard drive is less than 2GB. To access the settings for this, click Tools >> Options.
For a simple calculation of drive space required, continuously recording at 248kb per second will equal about 1.8Mb per minute. 112MB per hour, or 2.6GB per day. A 500GB drive will store approximately 6 months of recordings.
