password reset prevention

[peekaboo]

i recently learned how easy it is to reset passwords without knowing the original password.
this was very useful for me as i was able to reset the administrator password on a machine in my lab to which i did not have the password (i AM the administrator).

i won't explain how as i don't want this thread closed but i'm referring to a boot disk that makes it possible, and i'm sure the experts here know what i'm talking about.

anyway, this now worries me.
is there any way to prevent others from using this on one of my machines?
better yet, any way to ensure that i (and the department computer administrator) are the only ones who can reset passwords?

[sgtspector]

If its feasible you can disable boot from cd or floppy and usb drives. Then make sure no one has physical access to the interior of the case so the bios can not be reset.

[DynamicTech]

Keep your computer under lock and key. If anyone can physically touch it, they can get in it. At least i can :)