The simplest way to recover the contacts is through Google. Access Google Contacts and import the backup with the contacts. Then on phone go to Settings > Accounts > Google. Add the Google contact to the phone (the one used to log in on Google Contacts) and enable SYNC for Contacts. Make sure you are connected to Internet while doing this and the contacts will appear on the Contacts section. However, you can't recover all the lost files and apps. If the images were stored on the SD Card, then connect the SD card to PC and use Recuva to recover the images.