Reclaiming Server Hard Disk Space - from logs and such

See
http://blogs.technet.com/b/sbs/archive/2010/03/02/recovering-disk-space-on-the-c-drive-in-small-business-server-2008.aspx

has notes for 2003, including the Cleanup Wizard for WSUS
http://technet.microsoft.com/en-us/library/cc708578%28WS.10%29.aspx