Hello,
I've recently attempted to install Kali Linux 2016.2 in Virtual Box.
I got the .iso file (x32 bit) and afterwards did all the basic pre-install junk
with virtual box and enabled "pae/NX" in the virtualbox system settings.
Afterwards when I tried to run a 'graphical install' the entire VirtualBox seemed to just 'freeze'.
There was an underscore ( _ ) in the bottom left hand side of the screen that stopped blinking about three minutes into the installation.
After about 20-25 minutes I 'powered off' the virtual machine, turned it back on, and then tried to do a regular install.
I got the same results -- just a frozen _ at the bottom left-hand side of my screen.
Attached is a picture of what I'm talking about: KaliError.jpg
A larger version (imgur): http://i.imgur.com/dR5Hbin.png
I'm not sure if this helps but the last message that appears right before the hang
is something along the lines of: "Trying to (free?) the frame buffer..."