Deleting unneeded files in Windows XP

Sites this information was copied from:
NetworkTechs.com

Delete files at your risk!!
Always be sure to have a good backup.

Easy
  c:\windows\$Uninstall******$
    to uninstall a windows update
    (do not delete $hf_mig$)
  c:\windows\srchasst
    the XP Search assistant
  c:\windows\downloaded installations\
    the installers for some programs you download and install,
    so you can repair it or update its components later
  c:\windows\system32\usmt\
    the File and Settings Transfer wizard
  c:\windows\msagent
    MS Agent is a stupid little wizard thing
  c:\windows\java
    MS Java components that don't work well
  c:\windows\mui
    allows you to switch between multiple languages
  c:\Windows\SoftwareDistribution\Downloads
    the source setup files downloaded
  c:\Windows\Downloaded Installations
Caution
  c:\windows\system32\dllcache\  - Just the files
    holds a backup of every system file that windows uses
  c:\windows\servicepackfiles\i386\  - Just the files
    has the new files that were updated by a service pack
  c:\windows\driver cache\i386\
    windows uses if you ever add or remove windows components and things
    like printer drivers
  c:\windows\inf\
    contains a lot of windows drivers