How To Kill a Python

[Ben Ocean]

Hi;
I continually run into problems adding new software to my server that is 
dependent on Python because I have 2 versions, one of which is completely 
unnecessary; namely, 1.5.2. I want to kill it, or at least make it so that 
when Python is called it automatically calls 2.1 instead of 1.5.2, but I 
don't want to screw anything else up on the server. How should I go about this?
TIA,
BenO