Aomei is very easy to use. Isoo is probably the simplest of all, but it is very stripped back so Aomei is still the top recommendation for something that does the job and is very easy. Aomei standard edition (free) is fine for most purposes.
I think all or most of the easy image applications have been mentioned. They are best for complete system backups.
I know they can do other things, but to keep it simple, the image backups are best used for system backups.
If you want a dedicated file and folder backup that is very easy to use and very efficient and fast, then I haven't found anything better than Bvckup 2. It's a very small, light application that does an amazing job at what it is designed to do. The only thing is, it's not free. But it could be worth your while.
If you don't want any third party programs, you can just use DISM's capture-image. With ESD/recovery compression, it is very efficient.
If you want something more user friendly, then just go with Macrium Reflect or AOMEI Backupper.
If you happen to have a Western Digital Hard Drive (my favorite hard drive brand) then you can download Acronis True Image for Western Digital edition for free, which is the best backup tool in my opinion. Of course the free version has limitations, like no encryption, no universal restore, but the basic features like scheduler and bootable recovery media creation are all there.
For image backups: Macrium Reflect Free (there is nothing better)
For File/folder backups I use three different backup software (as updates are provided, not all may work as expected, so better safe than sorry): Bvckup2 (paid), FreeFileSync (free) and SyncFolders (free & absolutely great software). Links below.
FreeFileSync: Open Source File Synchronization & Backup Software
SyncFolders - an easy tool to synchronize or backup your files and folders
I installed an older version of True Image a while ago and it was fiendishly difficult to uninstall. The uninstaller left behind disk filters which were very hard to remove and could render the PC unbootable if you don't know what you are doing. Acronis support was useless. See Solved - Safe Removal of Acronis True Image Drivers | Windows 8 Help Forums
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