Fix the backup procedure on 'My Computer' selection.

I tried to choose the backup drive on another drive and then select "My computer" for my selection instead of "Smart Selection", then I tried to choose only a folder with 2 files of each 28Kb and 26Kb, and click next. What happened is, the estimation data is reading entire my hardisk. I think it read on "Smart Selection" (what files that are selected) plus on what I choose on "My Computer"?