Thanks BOAC.
When my desktop crashed i was essentially given two options, to back up and reformat, or reformat. I chose the former. I plugged in the new external hard drive and it backed up. There were no options and my PC was in no state to select anything. I just assumed, maybe incorrectly, that the back up would be readable to Vista.
I think Seagate tech support is my next call in the morning. The likes of PC World, I-yogi etc have no idea. The data is not sensitive, but it is important, i'd gladly pay anybody's fee but having spoken to around 30 people now i'm starting to think a solution is not available. If this file were full of something say the police were interested in i'm sure they would find a way, any coppers out there?