Apple IIe Duo Disk Problem

["Roger Hurwitz" <roger_a_hurwitz@ccm.jf.intel.com>]

I just purchased an early Apple IIe with Duo Disk and monitor at a rummage
sale along with some interesting software.  Unfortunately, it came with no
documentation or anything resembling system software.  It appears from the
game software that I should be able to boot the machine from the game disks
themselves, but when I try putting the boot disk in the left-side drive of
the duo disk and powering on the computer the drive lights up, "chatters"
for a few seconds, appears to be spinning, but the system just hangs after
displaying the Apple ][ logo on top.  When I disconnect the I/O card the
unit boots nicely from ROM, but that is somewhat less satisfying than
having the drive unit operational.  The machine has an SMT Vidtech 80/64
card in it if that is relevant.  In terms of a frame of reference, I have
never owned an Apple although I am very familiar with PC h/w and s/w.  Any
help would be appreciated.

Thanks,
Roger Hurwitz
roger_a_hurwitz@ccm.jf.intel.com