I created a nandroid backup and copied the files to my computer
boot.img
cache.ext4.tar
data.ext4.tar
nandroid.md5
recovery.log
system.ext4.log
ta.img
I deleted the files on my phone to save space and now have copied them back. I used Online Nandroid Pro and not sure how to actually get it to do a complete restore?
I once extracted single apps and apps data using a normal archiver explorer in my Arch Linux system. In Windows, 7-Zip FM or Winrar should do the trick.
Obviously it is quicker done if you restore the full backup all at once with a custom recovery (but I believe you already merged the archive parts the backup is done in), but I once made a backup after the system launcher went to a systematic crash, so I couldn't do anything, and doing a full restore would led to the very same problematic, so I had to get back the data of the apps I wanted to restore that way.
Just open the .tar files, they are compressed archives. data.tar contains what the data folder contains in your Internal Storage: upon all the folders, data/app contains the apk of the applications you have installed, and data/data their saved data, which is you may want to restore. Inside that folder, every app has its dedicated folder (e.g., data/data/com.google.android.apps.maps for Google Maps). Copying it in your data/data folder in your phone with a root file manager will restore the data for that app.
Again, for a complete restore, just copy the whole packages (supposing you left them untouched) in the directory they were (to find out which it is, do another backup and you will see where it is created), boot into a custom recovery like CWM Recovery and do a full system restore, pointing to where the backup is located in your phone.
To restore a nandroid backup, the device cannot be in "normal operation mode". You have to boot into your (custom) recovery (see our tag-wikis on: recovery-mode / clockworkmod / twrp), from where you can trigger a full restore. With ClockworkMod Recovery, it is e.g. found in the Backup & Restore sub-menu.
Stock recoveries don't offer taking/restoring Nandroid backups. But as you were able to create one, it's pretty safe to assume you've also got a custom recovery installed to your device.
