you should run a disk cleanup. it safely removes files on your computer that aren't needed.

simply press start,
then go to programs, then accessories, then system tools, then Disk Cleanup.
Important: Read EVERYTHING before you check the box to have it deleted. It will tell you if its safe or not for you to delete.


after that, you can run a Disk Defragmenter to make your computer run faster.


hope that helps :]