First step is to install QEmu on your Linux Box, I'm using Fedora and a modified yum configuration to use mi DVD to install software, to install QEmu do that
"yum install qemu"
after that the Second Step is download FreeDOS from http://www.freedos.org
download fdbasecd.iso
Ok... now we have to do an image of qemu to install FreeDOS for do that write:
qemu-img create dos.img 20M
where dos.img is the name of harddisk and 20M it's the space left to install DOS.
Third step: install FreeDOS on dos.img using qemu... for this write:
qemu -m 32 -std-vga -hda dos.img -boot d -cdrom dbasecd.iso
Here you are using 32 MB of RAM with standard VGA (VESA) with a hard disk of 20 MBand booting form the FreeDOS image CD.
after that you will see...

Ok... then install FreeDOS over the 20M HD, of course you have to create FAT16 partition and format .-
After do the install process...


After try to boot from the DOS disk...
use this command
qemu -m 32 -std-vga -hda dos.img -boot c
ant try to use some utilities


Now... you are ready to run your DOS games... HOW ?
First create an ISO image of your desired game... use the mkisofs utility.
First Copy and Unzip the game
[mariotpc@andrew pre1]$ dir
Prehistorik\ 1.zip
[mariotpc@andrew pre1]$ unzip Prehistorik\ 1.zip
Archive: Prehistorik 1.zip
inflating: --------.ANS
inflating: CHKLIST.CPS
inflating: COURIER.APP
inflating: FILESA.CUR
inflating: FILESA.VGA
inflating: FILESB.CUR
inflating: FILESB.VGA
extracting: GRAWAGA.CFG
inflating: HISTORIK.CS
inflating: HISTORIK.EXE
inflating: HISTORIK.NFO
[mariotpc@andrew pre1]$ dir
--------.ANS COURIER.APP FILESA.VGA FILESB.VGA HISTORIK.CS HISTORIK.NFO
CHKLIST.CPS FILESA.CUR FILESB.CUR GRAWAGA.CFG HISTORIK.EXE
[mariotpc@andrew qemu]$ mkisofs -o pre1.iso pre1/
I: -input-charset not specified, using utf-8 (detected in locale settings)
Total translation table size: 0
Total rockridge attributes bytes: 0
Total directory bytes: 0
Path table size(bytes): 10
Max brk space used 0
569 extents written (1 MB)
[mariotpc@andrew qemu]$ dir
dos.img dos.iso max-user-freq.orig pre1 pre1.iso
After do that run QEmu with this command
qemu -m 32 -std-vga -hda dos.img -boot c -cdrom pre1.iso
And ready to play the game....!


Notes: the CD drive is often mounted on d: drive... just go to this drive and run the exe file.