Small lockout program

I have a couple of very smart kids and I need a very simple program to
password protect a couple of software programs that I use for business.
These programs do not come with a password protection option and I was wondering if there is a freewareprogram out there somewhere that would enable me to put a password on the start up file for the program.

For example if I want a password on say a personel contact manager that has a start command of PCM.exe , is there a little program that whensomeone clicks on the Icon for this program, a pop window will apppear asking for a password and without the right password, the program will not open. (This is just an example only. I have a couple of REAL programs that I would like to do this to.)

Any information on this would be greatly appreciated.

Ray.