IPhone Stolen, Apple ID stolen

Question

HI All,
My 2 year old iPhone5 16gb black was stolen last night. Minutes after, I activated iCloud find my iPhone feature on my Mac, and it said my phone was offline. Few hours after, someone reactivated my phone and deleted it from iCloud. I know this because I received Apple ID email and all sorts of prompt on my Mac saying my ID was invalid.(A sound was played, the phone was located, and it is deleted from iCloud) Lucky but not fast enough, I reseted my ID's password, but my phone is gone from Find My iPhone list.
So, the question is, how easy it is to crack someone's Apple ID, and if it isn't very difficult, what different does it make to have the lock phone feature or not?
I thought of DFU mode, isn't it true, one don't have to start the phone to enter DFU or recovery mode?(not sure the differences), and reset the phone? So is it possible to lock these features, so to render the phone a true brick? (Open for corrections.)
The underline up there, the email says the location will be availible for 24 hours, but when I go to iCloud, it's just gone, what happened there? Will I be able to track the last known position?
Also, does anyone know how to restore iphone5 backups back to iphone4? I have the backup file, but don't know how to put them back into the old iPhone4.
Apple, you can't tell me and us"Just dont lose your phone or buy extended Apple care", that's not fair.

Answer 1

Are you saying that you did not have a passcode on the device? If they were able to enter your device, they could have reset the Apple ID password. DFU mode would not matter if Find My iPhone was still active.
As far as restoring the iPhone 4 to the iPhone 5 backup, it probably won't work. The latest iOS for the iPhone 4 is iOS 7.1.2, and the iPhone 5 more than likely had a higher iOS. You can restore a backup with an iOS lower than the phone you are restoring to, but you cannot restore an iOS backup that is higher than the phone's iOS.
Lastly, Apple does not participate in the forum, this is a user to user forum. And, extended Apple care would not cover loss or theft of a device. Extended Apple care is nothing more than an additional year extension of the standard 1 year manufacturer warranty, which does not cover loss or theft as I stated above.