Isaac Cox in West Virginia

I am back to doing genealogy research after having to take a break of several years because I just didn't have time to spend on it.  I'm starting with my Cox line and have come upon an interesting book online called The Cox Family in America that gives a lot of history on the several Coxes that came to America from England, Sweden, Holland, Scotland to name some.  And even includes early genealogies for many of them.  From what I understand Coxes from these different lines spread far and wide across America.  Since certain names were so common in different lines (like Isaac, Thomas, Wm), I still haven't connected my Isaac to which one he  may have descended from.  What I do know is that his folks migrated from Greene Co, PA over to the area of Tyler Co., WV by 1850 when he shows up on the census there.  From what I have gathered he was born about 1795 in PA and married Mary Wise, probably also from PA and probably married they were married in PA but I haven't found a marriage certificate.  

What I have come to seriously question is that my Isaac was the son of Michael and Jeruthea (Brooks) Cox in Ohio Co, VA(WV).  I see a number of folks have put them on their trees as being his parents, but the more I dig the more I doubt this.  They did have a son named Isaac, BUT his place of death is different than my Isaac, who I know to have died in Pleasants Co, WV.  Which is in keeping with him living in Tyler Co, WV in 1850 and I believe Pleasants Co was created from parts of other counties, including Tyler.  Having grown up in Pleasants Co and living in the same area where my grand and great-grandparents had lived for years I know which is my Isaac in WV.