need your help for reimage & backup windows 7

[Arshad Niazi]

Assalamu Alaikum
Hope you all will be fine by
the Grace of Allah Almighty.
Please guide me how much space is required for backup
And for reimage how can I use these if I reinstall windows 7
How to make reimage
difference between reimage and back up
Which is best copy on dvd or in usb….
Please check attached files
Thank in advance.

[Arshad Niazi]

sir still waiting for your kind experts opinion please