Hi jmm and welcome to Windows 7 Forums. You can also press F1 and the help box should come up. Type in num lock or shortcut keys or something to that effect. You should get some idea's there. Please let us know.
Hi Mike. A num lock key will be present when you have both the numbers along the top of your keyboard plus a seperate number pad. The num lock button will control the seperate number pad and enable or disable it. Usually you have to press and hold the num lock key for 5 seconds or so and then you'll get a message come up to turn it on or off, or you'll just hear a beep (it's not in your head it's real lol) and that signifies you've turned it on or off.
Once you have determined the correct key or key combination (Function (Fn and associated keys (purple, blue,etc.,) You may want to reboot into your system BIOS (setup utility) and see if there is a predetermined Num Lock On At Boot setting which can be altered. Additionally I believe that there is also an associated registry key that windows uses to determine the correct setting for the Num Lock feature (on or off) after logon. Check google for that information. Welcome to the forums and thanks for joining our community Best Wishes Randy