well, it's always a good idead (if you can, of course) that you separate os partition and data partition. if something goes wrong, you just format/replace system but data remains on other partition/disk.
In your case...i would just redirect the user folder to be on f disk (500 gb) or just redirect documents/picture folder to f disk. and backup that folder(s). It is option to backup image of system but you must do that periodically (on 1 week) because if you do it just occassionally, sometimes the image gets "old". When you restore the image, it may need some time to download all the new updates, drivers etc etc.
There are many free programs to do just backup of folders or backup of system drive completely. I use easeus todo free. Mainly to do daily / weekly backups of my documents/pictures folder to NAS drive.
