A great program everyone should have on their PC for removing stale cookies, temporary files etc. is CCleaner from Piriform. http://www.piriform.com
When it first starts up allow it to save typical cookies (Google, Yahoo etc) then select CLEANER from the left hand menu. You will see a list of things it will remove based on age. History is one you may want to uncheck if you like to save your history for returning to websites.
One great feature of CCleaner is under TOOLS > STARTUP - allows you to pause or remove all the programs loading up at start that crowd your system tray (down by the clock) ... Except for your antivirus, almost everything loading up at start-up is there to benefit the company that installed them and not you. But if unsure what a startup program is, simply disable it (them) and reboot and see if you are affected.