Mario,
Since I had already placed the order and it was already shipped out from the warehouse,I thought that I would just wait for the new router to see what happens.
When I unpacked it,the manual had these really elaborate instructions on how to set it up...such as typing in an address in the search bar,contacting my cable company for the Mac Address..etc.,....which was a nightmare.
I then called Comcast and explained the whole proposed scenario from the manual and she told to forego all that,and just execute the procedure you mentioned and it was just plug & play.
More than likely I guess,your 1st method you mentioned would have worked(on my old router)...but I'm not going to make a fuss and disrupt my set up,just to save $20...by returning my new router.
The way I look at it,I'll have a back-up router...just in case.
Thanks again for all of your help!By the way...the MagicJack phone is great and I'm saving myself $270 a year!
911 calls are an extra charge,which is odd...but I have a free cell phone for that.
-Thom