I've been using Ubuntu and Win XP on my laptop for about 2 years. The
only Windows app I have needed is the Cisco VPN client (the Linux
version doesn't have the statefull firewall my job requires). I have
Win XP installed in Virtual Box to take care of this problem. I can
have Ubuntu and Windows running at the same time - no reboots.
Perfermance of the Windows session depends on the resources you give
it in Virtual Box. Mine is set up as a 10 GB hard drive, 512 MB RAM,
16 MB video RAM. And yes, you will have to install Windows into you
Virtual Box session. Just my 2 cents worth.