P key Crash

Blender 2.65, in 3D window edit mode the P key separates as I expect it to, but in object mode it immediately crashes Blender to a nonresponsive flickering display. Admittedly I am on windows XP but every other feature in 2.65 works very smoothly on my system… What is the P key a shortcut for, so I can disable it in prefs?

P starts the Game Engine