You could just use an ancient laptop running "real" DOS. But as the others have said, you might be able to with the default bootloader, though you may be better off using GRUB or some third-party bootloader.
I remember trying one called "GAG" once, it was okay, except it only works if your hard disk is EIDE, not SATA.
I do this a lot for multiboot systems. Three partitions will be needed. In this case Two FAT and one NTFS partitions. First FAT partition will be the boot partition and will house the bootloader such as Grub or LILO. The second partition should be Win7's NTFS partition then the third FreeDOS.
GAG is a nifty bootloader. I use to use it on a few older machines.
Extended Operating System Loader (XOSL) is the world's only full-featured free boot manager with a real, easy-to-use and full-blown graphical user interface. Click the screen shots link to see what XOSL is like, and decide for yourself!
Main Features
Look & Feel
User-friendly Graphical User Interface
Full windowing system with mouse and keyboard support
Resolutions up to 1600x1200
Configurable mouse speed
A set of color schemes
Several color adjustment options
Password protected boot configuration and settings
Restart/Reboot/Shutdown
...and more...
Booting Features
Up to 24 boot items
Microsoft file system partition hiding support
Storing additional keys before booting
Activate partitions (one per system or one per HD)
Automatic booting (with timeout)
Auto boot last operating system
Password protection per boot item
Boot master boot record on any drive
Boot DOS/Windows 9x on any drive
Hotkey per boot item
Support for hard disks larger than 8Gb
[XOSL 1.1.1] Coexist with virtually any other boot manager (boot original master boot record)
[XOSL 1.1.2] Run Ranish Partition Manager 2.38 beta 1.9 from XOSL, without first booting an OS
[XOSL 1.1.2] Master boot record virus protection
[XOSL 1.1.3] Swap drives
[XOSL 1.1.5] IDE CD-ROM booting by including Smart Boot Manager
...and more...
Comments
(I have DOS & win2000 and it works perfektly)
I remember trying one called "GAG" once, it was okay, except it only works if your hard disk is EIDE, not SATA.
GAG is a nifty bootloader. I use to use it on a few older machines.
And its GPL with source code available
Archive of Original site with downloads
http://www2.arnes.si/~fkomar/xosl.org/
Info & History:
http://en.wikipedia.org/wiki/XOSL
XOSL 1.1.5
Main Features