Should I use Python 2.7 32 bit or 64 bit with Windows 7
I recommend the 32-bit one unless you are going to exhaust the address space. Many third-party modules like OpenCV and Numpy are considerably easier to install with 32-bit Python. (You can build those modules from source to get them to work with 64-bit Python but that's probably more time and effort than necessary in most cases. Sometimes there are unofficial 64-bit builds but they aren't supported by the module authors.)
While you probably don't need those modules for Django, if this is your personal computer and you might install them for a different project and don't want to deal with two Python installations on the same machine, I would choose 32-bit.