Recovering email addresses from windows 7 backup?

I recently had a blue screen of death with windows 7 which required a reinstall. On reinstalling, window 7 automatically backed up all data and programmes in a folder called window.old. I would like to find all my email addresses in this folder and migrate or copy them into my new install of mozilla thunderbird. However I don't know what file to look for. I would also like to copy old email messages across aswell but again am not sure what I'm looking for. Can you help?