Different network cards, different video cards, different sound cards etc etc. Unless its the same make and model chances are there will be trouble. How much trouble is the determining factor, if they are completely different I would say probably not a good idea to try it, if they are close you could try it and see what happens, you may only end up with a few things in device manager that are not recognized and may be able to fix by updating the appropriate drivers.

Generally speaking its always a better option to start fresh and just restore your data. Restoring applications and registries are not always the most successful unless its to the machine you backed up from.