My only complaint with Windows 7 here is that (IMHO) the current windows explorer shell blows, which affects open/save dialogs and the file manager.  But even that isn't too difficult to work around as there are some great utilities out there.

But as far as stability, compatibility and the whole thing not coming down when there's an issue (BSOD), I think Windows 7 is really awesome.

Okay... another thing... UAC is NOT awesome but easily tamed to be less intrusive or you can turn it completely off if you are skilled enough to get yourself out of problems :)

But back to the topic at hand.  CCleaner is very safe at the default settings at cleaning out temporary files if you don't feel like hunting all over the place for them.  I'd also suggest defragging from time to time but for most users that's on a schedule witht he built-in defrag anyways.  I use auslogics Disk Defrag.

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