BOAC,
Most Mobos and Hard Drives are not Win98 compatible, much less DOS compatible. With the latest Hardware, you will find that they exceed the limitations of Hard Drive Size and with objects like USB, just not compatible.
With WinXP out, there is no need to go back to DOS. I would not bother to keep Win3.1 or Win3.11 around any more.
Now any DOS 5.xx or higher will work with Win3.1/3.11.
Take Care,
Richard