If VMWare Blue Screens when you try to access a USB Scanner, do the following:

In the folder where you created your Virtual Machine will be a .vmx file, open this file for editing in notepad.exe.

Change the following two lines:

virtualHW.version = "6"
usb.present = "TRUE"

Add the following line if not already present:

ehci.present = "TRUE"

Save the file - and relaunch your Virtual Machine.  The scanning device will now work - and no more blue screens.