thank you, pressing fn+numlk solved my problem, at least temporarily. I installed LogMeIn and had no problem. then I installed windows live mesh for sharing files and remote control, and sometime after that, started having this issue. i've disabled all that software, but the problem still persists. interestingly, this is NOT a problem when windows first boots up -- I am able to enter my password without a problem. the problem starts sometime after I login, leading me to believe that some software that loads up on login is making this happen. once the problem has manifested itself, if I lock my computer (windows key + "L"), I cannot unlock it as the numLK key is now on, unbeknownst to me.
i will now try rebooting and see what happens. at least I now have a way to flip the fn key. phew.