Disk Cleanup freezes during the Compressed File Phase: This edit corrects the problem:

Disk Cleanup - Compressed Old Files Freezes (Line 48)
http://www.kellys-korner-xp.com/xp_tweaks.htm

To use the Regedit: Save the REG File to your hard disk. Double click it and answer yes to the import prompt. REG files can be viewed in Notepad by right clicking on the file and selecting Edit.

Disk Cleanup Tool Stops Responding While Compressing Old Files
http://support.microsoft.com/default.aspx?scid=kb;en-us;812248

How to Automate the Disk Cleanup Tool in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q315246

Restore Disk Cleanup - cleanmgr (Line 84)
http://www.kellys-korner-xp.com/xp_tweaks.htm