You haven't mentioned what version of Ghost you are using, but I would assume it's 11.5.1.2266 and you are working with the WinPE version that comes with it. If this is correct, perhaps you should consider using a later version of WinPE as described here:
https://www-secure.symantec.com/connect/articles/creating-and-using-winpe31-image-gss-251
This should enable you to use Win 7 drivers instead of Vista drivers, just in case you can get Win 7 32 bit drivers for your machine.
If I recall correctly, the Ghost64.exe program is intended for hot imaging of running 64 bit operating systems and was not intended as a 64 bit version of Ghost32.exe. However, have you checked the Ghosterr.log file? There may be another reason for the freeze. Nevertheless, I still recommend checking the chipset and looking for drivers on the vendor site. Finally, bear in mind that you must use drivers appropriate to the version of WinPE you are using, regardless of the version of Windows you are trying to image.