Questions -isolation transformer

[EwJ]

Hi, can anyone help with questions regarding wiring for an isolation transformer?

Chassis has a two-conductor power cord (pic  below)that plugs into an ungrounded power strip (2-prong plugs-pic below) that is wired (2 conductor) to the output of an isolation x-former.  The isolation x-former input has two wires going in from the back of the machine from a recessed 3-conducter power receptacle (like ones used in a pc power supply).  The middle wire (ground) from the receptacle was hanging loose. 

Q1a) Does the middle wire (ground) connect to the iso xformer housing via one of the iso xfomer mounting screws (bottom of frame)? pic below
Q1b) Would it be advisable to use the 'extra' set of wires that are soldered to the power receptacle for hooking to a PC power supply? (or would it be better to run a separate input/cable for pc pwr supply) (i would assume that it would be a bad idea to try to power pc from 'behind the iso xformer').
Q1c) Are there any other grounding/safety features that need to be in place to avoid injury, death, the letting out of the magic smoke from monitor, pc, and other electronics, etc.

edit: removed unrelated questions.