Hi Snoopy1947,
I am a standard flight simmer just like you. I have no connection with Laminar Research and I am no expert on X-plane.
From all of my readings of the Q&A's in the this forum, I understand that you would struggle just to run version 10.
Have a look at the current minimum specs required for version 10 and even while you can, download the current Demo version of X-plane 10 and try it with your current PC unit.
I strongly suggest you will need to acquire a new PC. My suggestion would be an absolute minimum of an i5 processor, better still an i7 and use a nVidia card in preference to AMD. There a several YouTube videos making mention of the non use of AMD.
Glenn