Well big senior moment. I had reported earlier that I could not get the scope to work in VirtualBox and Linux. But it does work...if you get the right software.
There were three things that were key, I think. Hopefully this will help someone else:
1) Latest NI Drivers:
http://joule.ni.com/nidu/cds/view/p/id/1605/lang/en2) The Rigol USB drivers have the wrong USB ID or something on Linux is changing the ID (vendor=1ab1,pid=0588 in Linux/VirtualBox, the Rigol.inf file vendor=0400,PID=05dc). Of course, I was so smart, I changed the INF file and got it mostly working. WRONG. Use the NI driver. What that means is in Device manager, it should say "USB Test and Measurement Device" *NOT* "Rigol USB Test and Measurement Device". If you already have the Rigol drive installed, do an update driver, tell it to Install from a list and "Don't search I will choose the driver to install." If you have the NI stuff installed you should see two choices: Rigol USB Test and Measurement Device and USB Test and Measurement Device. You want the one WITHOUT Rigol in the name.
3) The VISA version of Ultrascope (this was my big mistake, using the "regular" version). See
http://www.rigol.com/templates/T_Support_en/resources.aspx?nodeid=639&contentid=1582. Even on a "plain" Vista install the regular version had small issues.
Of course, for Virtualbox, you need to go to the Devices menu and "connect" the Rigol USB device (this one will say Rigol and that's ok). You can also change your setup to add it automatically, but I'm going to assume you know how to do that.
Of course, I probably will never use the software but I wanted to make it work. I'm funny that way as are, I bet, a lot of us.
Cool!
P.S. Screen shot at
http://www.hotsolder.com/2010/04/rigol-ultrascope-under-linux-with-virtualbox.html