deselect items whose settings you do not want to drop;
In details:
Clear the history: Clears the list of visited web pages.
Reset Top Sites: Cancels all the changes made in the list of Top Sites, such as adding and securing sites. If you also clear the history list, then on the Top Sites page will reappear those thumbnails of web pages that are displayed immediately after installing Safari.
Remove preview image sites: Remove all Web pages preview stored images you've visited.
Clear the Downloads window: Clears the list of files that are downloaded from Web sites. Only the names are removed; the files are still on the disk, as long until you delete them.
Remove all Web sites icons: Removes website icons - small graphical images that can help to recognize sites on the Internet. They are in the address bar in Safari bookmarks list, and other places. These icons are stored on your computer.
Remove saved names and passwords: Removes user names and passwords that Safari automatically enters on Web sites that require authentication (if the AutoFill feature is turned on).
Delete the text auto-complete web forms: It removes personal information (such as phone numbers) that Safari uses to automatically fill out forms on Web sites (autocomplete if enabled). When deleting autocomplete data information from the directory is not removed.
Close all Safari windows: If you do not close all Safari windows, then using the "Back" and "Forward" unauthorized persons will be able to view the web pages you have opened.
Reset location warnings:It erases all the information about your location, which has been stored by websites.
Remove all site data: Delete cookie files, information about your activity, and other data that have been stored by websites on your computer.
