Description of each option in Disk Cleanup. This should help you decide which ones to cleanup.
Temporary Setup Files - These are files that were created by a Setup program that is no longer running.
Downloaded Program Files - Downloaded program files are ActiveX controls and Java programs that are downloaded automatically from the Internet when you view certain pages. These files are temporarily stored in the Downloaded Program Files folder on the hard disk. This option includes a View Files button so that you can see the files before Disk Cleanup removes them. The button opens the C:\Winnt\Downloaded Program Files folder.
Temporary Internet Files - The Temporary Internet Files folder contains Web pages that are stored on your hard disk for quick viewing. Disk Cleanup removes these page but leaves your personalized settings for Web pages intact. This option also includes a View Files button, which opens the C:\Documents and Settings\Username\Local Settings\Temporary Internet Files\Content.IE5 folder.
Old Chkdsk Files - When Chkdsk checks a disk for errors, Chkdsk might save lost file fragments as files in the root folder on the disk. These files are unnecessary.
Recycle Bin - The Recycle Bin contains files that you have deleted from the computer. These files are not permanently removed until you empty the Recycle Bin. This option includes a View Files button that opens the Recycle Bin.
Temporary Files - Programs sometimes store temporary information in a Temp folder. Before a program quits, the program usually deletes this information. You can safely delete temporary files that have not been modified within the last week.
Temporary Offline Files - Temporary offline files are local copies of recently used network files. These files are automatically cached so that you can use them after you disconnect from the network. A View Files button opens the Offline Files folder.
Offline Files - Offline files are local copies of network files that you specifically want to have available offline so that you can use them after you disconnect from the network. A View Files button opens the Offline Files folder.
Compress Old Files - Windows can compress files that you have not used recently. Compressing files saves disk space, but you can still use the files. No files are deleted. Because files are compressed at different rates, the displayed amount of disk space that you will gain is approximate. An Options button permits you to specify the number of days to wait before Disk Cleanup compresses an unused file.
The above information is extracted from article KB315246 titled "How to Automate the Disk Cleanup Tool in Windows XP"
http://support.microsoft.com/kb/315246
© 2007 Microsoft Corporation. All rights reserved.
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Regards,
Ramesh Srinivasan, Microsoft MVP [Windows Shell/User]
Windows® Troubleshooting
http://www.winhelponline.com
Files to delete on "disk clean"
-Download Program files
-Temporary Internet files
-Setup log files
-Temporary files
-Compress old files
My newbie question> Which files are ok to delete regularily and which ones
should i leave alone?
