|Do you have the original windows cd(or failing that one of the right product version and service pack)? If so I would suggest putting the cd in the drive an goining to start>run and typing it "sfc /scannow". It will check that system files are intact.|
Can you run this command from the command line(start>run>cmd) and post the results(you can copy from the commandline right click>mark>select text>right click and the text will be copied).
dir /b/s %systemdrive%\spoolsv.exe
The results should look something like this:
If the file is intact it may be possible to tell sc where the file is using binpath=.