If you want to disable it you could edit the registry (assuming you're running windows)... go to start, and in the search box type regedit and then click on regedit.exe when it appears. On the left side, expand the following categories:
HKEY_CURRENT_USER --- Control Panel --- then click Keyboard
On the right you will see an entry called "InitialKeyboardIndicators". If you double click on it you can change the value to one of the numbers listed below:
0 = Num lock is turned off upon logging on
1 = Num lock is disabled
2 = Numlock is turned on upon logging on
If you change the number value to 1 num lock should be completely disabled. If you don't want to completely disable it you could use a program like SharpKeys (https
/sharpkeys.codeplex.com/) to re-map the num lock key to something farther away from its current location so that you won't press it accidentally