Copying old photos from an iPhone to a PC
If you are able to view the photos in Photos app, an easier approach would to use a cloud storage service such as Dropbox or Google Drive.
Just create a free account with either one of them, install the iOS client app. Both the apps offer photo sync service where they upload the contents of Camera roll onto their server.
Once you have all the photos backed up, you can simply install the client app on your PC and sync off the photos to your computer.
Dropbox - iOS app
Google Drive - iOS app