windows 7 / 64 bit / is taking to long to shut down, and shuts down on its own randomly.

most likely due to power settings is why it shuts down randomly? do you mean it shuts off or shuts itself down? as far as slow shutdowns most likely programs hanging in the background waiting to close. your best bet is to use msconfig.exe to remove un needed startup programs as well as any other useless background services. that and a nice defrag