as far as i know, the DR-DOS project can emulate MS-DOS perfectly. as far as wine and wineX go, wineX is closed source, so you are limited to what they give you, plus you pay for it using a "one month at a time" microsoft style licence agreement.
wine on the other hand is open source, so theoretically you could just take a look at the code and go 'hey guys, here's what to do to make it work perfectly'. of course windows itself is closed source so emulating it would be guesswork by and large.
as i say though, there are totally transparent ways to emulate DOS in linux or so i have heard (never done it myself).
If i were you, and i wanted to dual boot, i would dual boot with just one copy of windows. either win2000, winNT4 or win98, whichever of those you actually have would probably be the best choice!
