Thanks to annoying Google Update features, I decided to run "msconfig" in my vista.
I was surprised to find that windows defender was already there! Microsoft does take care of every customer as caring mom. :P
Well, I found this SSBkgdupdate.exe lined up for startup entry in msconfig. Doubly surprised, I googled the name to find so many results concerning it. The lesson: It does not need to be lined up for auto start up.