How to prevent stolen iPhone Jailbreaking/Hacking and Restoring?

Ok so I have a IPhone 6 plus, kids in my area are thieves, a lot of people find iPhones and try to own it by restoring it, factory unlocking, hacking it and jailbreaking it. I want to prevent that so how can I? Is iCloud good enough to lock them out, is find my iPhone good enough to track them down? Or do you recommend anything else?

Possible Iphone camera issue?

So on my iphone 5, my selfie's flip. Before I take the picture it all looks fine, but lets say if my hair is parted to the right, it shows just fine in the image but when I take the selfie is flips and my parted hair is on the left, is there any way to fix this?

Can I use my iPhone 5 sim card on the iPhone 6?

So I currently have an iPhone 5 with a 2 year contract for about $35 a month. I'm upgrading to an iPhone 6, can I take the sim card from the 5 and put it in the 6?
I heard that Telus (the phone company I'm with, as well as Rogers, Bell, etc) is making all iPhone 6 users have a plan that has to be $80 or higher. If this is true, is it possible to still have my $35 dollar plan on the iPhone 6 somehow?

I'm in Toronto, Canada if it makes a difference.

I NEED COMPUTER DVD TRANSFERRING PICS

So I took pictures of my friend yesterday and I edited them and all that and then I had them sent from my camera to my iphone to do some things to them. Like 20 min ago I plugged my iphone into the computer, got ALLThe pictures on my computer, put in an empty DVD that's meant for this, I clicked all the pics that I wanted onto the cd, clicked "move to" and then I clicked the DVD option that I had in the computer, and then it did that loading and alnalysing stuff and then that just went away as if it were done. So I clicked on the folder that said "DVD" and I named it senior pics so I know that was the one. NO PICTURES WERE ON IT, All THOSE PICTURES ARE DELETED FROM THE COMPUTER AN MY PHONE. I didn't click delete! Iv done this transferring to DVD stuff before and this has never happened! WHAT DO I DO?