Windows backup help

I just sold my SSD and it had my OS on it, I Wiped it clean with the windows 7 ultimate disk, so now I'm a little stuck. I want to install windows 7 ultimate into my HDD but I don't want To lose all my files that's on it. How do I do this? The Option that the windows 7 disk is giving me is "upgrade" and "custom (advance)" witch one should I pick
 

Custom

and then create a partition on the drive for windows (give it at least 100 GB if possible) No less than 50 GB

DO NOT delete any other partitions on the drive.

Boot from the OS partition, Grab your files, put them on another drive if possible, (external maybe?) and then wipe the entire drive and install windows, and put all your files into the single partition.

You will have

A) a backup of all your data

B) and entire drive to work with, with windows and your data

C) All your problems solved.