how to use netbsd with ubuntu?

[Mayuresh Kathe <mayuresh%sdf.org@localhost>]

as in a previous email, i need to use ubuntu as my primary desktop.
i researched various options via googling around as well as asking
this mailing list and it looks like the best thing would be to run
netbsd in a virtual environment. for the same, would "qemu" be
considered good enough? if it is, should i upgrade my system memory
from 4gib to 8gib? i have a 1tib hard disk, would running with a
256gib 'ssd' instead pose any unforeseen problems? thanks.