Windows has a defragger built in so in my opinion getting a 3rd party program to do it is a waste of space.  Also temporary internet files can be cleared through your internet options on any browser.  As for searching for tracking cookies or spyware that you might have i would recommend Ad-aware and/or Spybot Seach and Destroy. They both search the whole harddrive for malicious software, not just the internet cache and they are completely free - indefinitely.

If you want more free stuff in this kind of area then i would also recommend Zone Alarm firewall (it actually blocks EVERYTHING unless you tell it not to - rather than trying to be clever and work it out for itself - a window pops up and you have the choice to allow or block a program from accessing the internet and you can set it to one time only or have the firewall remember).  And then AVG Antivirus. which has updates free as well. 

So yeah - this is all free stuff - no strings attached no spyware installed or anything.  I used all of these on my girlfriend's computer over the weekend (because it was a bit messed up) and found 162 spyware processes or files with spybot, 42 trojan horses with AVG and revealed a couple more through them wanting to access the internet through the firewall. So yes - it works ;)

"In every colour, there's the light.
In every stone sleeps a crystal.
Remember the Shaman, when he used to say:
Man is the dream of the Dolphin"

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