Some internet security software packages do it themselves - when I reinstalled Firefox a few weeks ago (I uninstalled it completely after some issues and then reinstalled it from the downloaded latest .exe installation file), I didn't need to get all my passwords from my little notebook (an actual book).

Unless you reload the computer they will be on the HD just renamed as you never really uninstall a program, its just not possible for the OS to read it.

if you want to recover passwords try passview its a password recovery software that I use that works within seconds to recover passwords, but to save you have to copy and paste into word or similar program, it allows to print out the passwords along with usernames and email address just be sure to save somewhere safe