All A format does is write 0's to all sectors of a Drive.
A reformat, And then a (re)install of the OS would be a brand new install of windows. You will lose all data, programs and settings if you do not back them up.
A format doesn't write 0's to the disks. It basically just empties the file tables (as in: table of contents). This means the files are still there, but you don't know where
In simple terms, it just deletes all files (but they can be recovered with special software).
because wen i ryt click on c: and go to format it says i have to quit any disk utilities or windows showin the drive before formating but i HAVE clossed everything possible so am confussed