Parallels 8 (along with 7, 6, 5, and 4) always prints out of margin on certain DOS apps (cutting off the left side of the page). And no matter how I mess with the printer settings it still does it. Was able to fix the printer problem by moving to Fusion but now I have this corruption problem.
What can you possibly still be using from the DOS days that requires that much printing? Sheesh. Anyway, I haven't messed with printing much in it, but have you tried DOSBOX from within OSX as opposed to running these apps from within Fusion.
As for your problem, are you running an SSD or something else that Fusion doesn't like.
DOS works, QB requires very little code time to write simple apps. DOSBOX offers no comprehensive support compared to Windows. A shell in Win32 works great and works with anything the Win32 can authenticate with (any mapped drive). The setup I use works with the exception of Fusion hosing my VMs which is a minor annoyance since I take manual snapshots. It wouldn't bother me at all if the "auto" snapshots actually worked. It's set to take auto snapshots but they NEVER are able to repair the VM.