Open up the Reset Safari window again by clicking Safari from the top OS X toolbar and selecting Reset Safari... from the drop down menu. This time, observe the other options that are available. If you are running Safari 4, the options should be as followed: Clear history, Reset Top Sites, Remove all webpage preview images, Empty the cache, Clear the downloads window, Remove all cookies, Remove all website icons, Remove saved names and passwords, Remove other AutoFill form text, and Close all Safari windows –quite a few options to choose from.
Each time that you choose to reset Safari and clear cookies, you may also want to clear some of these other items as well. After a while, Internet files can start to build up on OS X and slow it down slightly. Here are some explanations for what these other things do:
Clear history - History is the browsing information that Safari stores for quick reference. For example, if you start typing a website URL into the Safari URL box, it may automatically bring up a website that you have previously visited. Clearing Safari history will reset this feature.
Reset Top Sites - When you open a new tab in Safari, it displays a grid of all of your bookmaked Top Sites. Resetting Top Sites clears your bookmarks and resets the grid to default.
Remove all webpage preview images - From the top OS X toolbar, select History and click Show all history from the drop down menu. This will bring up an iTunes like display of the webpages that you have recently visited. You may also notice that this history viewer has a cover flow like appearance. Removing all webpage preview images deletes these images.
Empty the Cache - The cache is basically data that is stored by Safari that is used to increase speed and performance of a web browser. Most commonly, data stored in the cache is in the form of request files.
The rest of the Reset Safari options are pretty self explanatory.