Removing current Python version and using another Python version
I think you probably have two options, barring a reinstallation of 2.7, which might be the easiest thing to do. 

You can include the following first line in every Python script:

#!/usr/local/bin/python2.6


Change the path to reflect the version and location of the Python you would like to use.

Alternately you could create a bash alias like:

alias python = '/path/to/pythonversion'


I would go with the first version myself.