So SP2 was "downloaded" but not "installed"?
To check this......
START>CONTROL PANEL>ADD REMOVE PROGRAMS....If SP2 isn't
listed then it wasn't installed. If it's listed it's
installed.
If it's not installed, suggest START>CONTROL PANEL>FOLDER
OPTIONS>VIEW>select "SHOW HIDDEN FILES and FOLDERS". Now
locate the folder WUTEMP and delete it. Go back and "DO
NOT SHOW HIDDEN FILES and FOLDERS".
Reboot (power off).
Assuming START>CONTROL PANEL>AUTOMATIC UPDATE; you have
AUTOMATIC selected, the SP2 download/install process
should automatically occur again.
If the process doesn't start immediately (for whatever
reason) START>ALL PROGRAMS>WINDOWS UPDATE; scan for
updates and SP2 should be identified. Commence
installation.
NOTE: You must have a minimum of 1.8GB of free space to
successfully install SP2. SP2 won't use up 1.8GB but
needs that much space to run the installation.