Lenovo Ibm Thinkpad R50e how to remove the power on password?

Boot up the laptop, and see if you can get to the BIOS (press F1 at the lenovo logo screen) and it should be in security. Quite often people add a POST password withour adding a supervisor password.
If you can't get into this because of a password, you're pretty much snookered, your best option is to speak to a tech friend to see if they can manually reset the bios (small internal battery being unplugged will usually help with this, however this is at your own risk).