notebook, on start up desk top won't load

I have the HP Pavilion g6.  On start up I get the HP screen and the spinning icon.  Trouble is the icon just keeps spinning and won't load the desk top, it won't respond to any key I press and I am forced to press the power button until it shuts off.  I wait a couple of minutes and power on and it usually works fine, but this is quite annoying, any recommendations on how to fix this?.