You run nt2linux.exe. It is an interactive utility. You select the information you want to export and produce an export.dat file. You copy this file to linux. It generally fit on a floppy if you do not have already networking connectivity with your linux box.
To copy a DOS floppy on your linux box, in the current directory, you can do
rpm -i nt2linux*i386.rpm
Then, you enter linuxconf and visit the "Miscellaneous services" menu and then the "Import NT configuration" sub-menu. At this point, check the help screen for further instructions.