Windows 2000 and the applications you run eventually create a dreadful jumble of files on your hard drive. Over time, the ratio of useless files to useful ones grows higher and higher. The following sections cover the files that you can delete with impunity and files you can delete with some caution.
Before attempting anything tricky in the war against unnecessary files, start by running Disk Cleanup. You can find this program at Start→Programs→Accessories→System Tools. When you start Disk Cleanup, you select the drive you want examined; then the program reports on the files that can be deleted from that disk. Depending on your configuration, these files may include:
Downloaded program files. Some Web pages send program files (such as Java applets and Active X controls) to your PC for temporary storage on your hard drive. These files aren't always deleted when you close your browser.
Temporary setup files. When you install a program, its installer often creates setup files in the WINNT→Temp folder or in a folder it creates, but may forget to clean them out when it's done.
Temporary Internet files. To reduce loading time for Web documents, Internet Explorer stores copies of previously visited pages in a Temp folder. (See Section 11.7.2 for more on these cache files.) Each file is small, but you can quickly accumulate hundreds or thousands of them over time.
Recycle Bin. If you turn on this option, Disk Cleanup will permanently ...