Memorex 32573060 Rotodrive 3pk - 1gb Media "delete files dropbox" Questions

...delete things from the drive but the available space on the disk doesn't change. I know I've deleted over a gigabyte of videos and documents but when I try to save new things in it, it says that it ...

...delete the Incomplete folder from my memory stick. Everytime I scroll over it for details and look in the folder, it has several weird symbols and file names, and tells me that it's 54 GB? I tried ...