Is there a GUI for IPython that allows me to open/run/edit Python files? My way of working in IDLE is to have two windows open: the shell and a .py file. I edit the .py file
Try Ptpython. It has much better integration with VIM. You can directly edit in VIM by just pressing V. It also allows browsing your history.. so you can pretty much code in the shell, and incrementally build up your code.
If you are already familiar with ipython, you can check the advantages of ptpython here:
https://www.youtube.com/watch?v=XDgIDslyAFM