I have a friend whose screen saver all of a sudden stopped working.  He is using my pictures slideshow, I set it to start after one minute - it doesn't start.  I hit apply and ok.  He and I are running xp.  When I use the same settings on mine, it works fine.  Whe he hits preview on screen saver it works.  Screen saver will just not time in.  He has done a system restore.