All sorted now, got Mrs W a iPhone 4 8gb form ebay for £170 it was someones unused upgrade phone on O2.
We rang Vodafone and they unlocked her old iPhone 3gs 64gb for free and then we both got our pack codes. (I'm now using her 3gs).
Ordered 2 x Giffgaff (O2) free sim cards and registered them online and transferred our numbers over using our pack codes which automatically cancels your old contract with your old phone network.
We are both using the £10 pay as you go goodie bags which you get:
500 UK minutes
Unlimited UK texts
Free giffgaff to giffgaff calls
I had bought an iPhone 3 off here for my mother a few months ago and set it up on giffgaff and she's more than happy, I reckon we are all going to save around £20 per month ish....
Once registered, Giffgaff send you another free sim so if you recommend it to a friend then and they register the sim then you both get £5 credit each....
More plans are available here SIM Card Deals | giffgaff.com
I'll let you know how I get on