Normally a host does back up the server but not the users files for your use for free.
The time to learn to make a backup is before you have a problem not after.
The indexing can usually be turned off in the control panel your host provides.
Or you could just simply upload a blank index.html page to each of those folders. If you take a peek in the forum sub folders where the scripts are you will see a blank index.html page in each folder. That is what they are there for to stop people from viewing your script files and start causing problems.
