Using the File Browser
If you are working with a lot of files or want to delete a lot of content to free up space then use the file browser. The file browser uses the same search criteria that controls which files display on the main content viewer. The file browser will display up to 200 files per page.
The file list view also lets you see exactly how much space each file is taking up on disk. When you delete a movie file iSpy will automatically delete the associated thumbnail and preview image and clear the data from the xml statistics file - so it's far better to do it through here than to delete the content via windows explorer.