Fantastic! No it does not ask to format as far as I am aware (when I attempted this last night). I don't mind reinstalling everything...just as long as the old data isn't lost.
Please use one of the free apps. I linked to and make regular images of your partitions.
Store the images , preferably on an external drive.
Any serious problems , use the Paragon or Macrium boot disc you ran off from within the program and restore the image ( even to a new HD if necessary ).