After screwing it up with a new version of Installer (don't touch Installer with a long barge pole people, stick to good old Cydia.. and u know what they say about curiosity and what it did to the cat, well I was the proverbial cat) I restored it in iTunes.
My shopping list for trying to dump the iPhone disk image to my PC in URLs is:
A tutorial from the people that know:
A guide to setting up an SSH server on Cygwin
And er, a newbie's guide to Cygwin
Wish me luck!