Hi Dwight,
May be your Sysprep has run too many times.
You can check in the windows7 by running the command SLMGR /DLV. In that you can see the rearm count, if it is more than 0 you can run the sysprep that is prepare for image capture job.
If the rearm count is 0. Sysprep keeps on running and the computer wont reboot.