This "Choose What to Keep" screen is new to Windows 8 and a departure from previous Windows install routines.
The choices you see here are dependent on the current installed operating system.
A complete discussion of "Choose What to Keep" screen options and availability is located here.
Because this is an upgrade installation of Vista w/SP1 you get to choose what to keep from the current installation.
Because this is a Vista to Win 8 full migration there is no option to keep any applications.