I want to dual boot with Windows 8 and Ubuntu. When I run the Windows Disk Management utility, it will only allow me to shrink the Windows partition from about 700GB to about 340GB (I haven't done it yet). It says that "You cannot shrink a volume beyond the point where any unmovable files are located."

The Ubuntu installer (from LiveCD) has no such qualms. I'd like to leave only about 100GB for Windows 8 but am worried about these "unmovable files." Does the Ubuntu installer move them? Or is shrinking the Windows 8 partition asking for trouble?