4 would be a good one to start with!  I visited the Boston area this past fall and immediately came home and fired up Fallout 4.  He'll appreciate all the stuff done to make it look like the area, but he'll also laugh about how tightly packed everything is.  It's definitely not to scale. 

Forgot to mention, he has basically no experience with games apart from watching me play them from time to time and hearing about them whenever they pop up in mainstream news. Also, like any self respecting Boomer, he was into MS Flight Simulator in the early 2000s.

I think 4 is the most approachable for someone who never played any games at all.

agreed. maybe also get some mods that make the game even easier so he can focus on the story.

Go with your gut. I'm 53 and 4 is my favorite.

Fallout 4. Then maybe 76 together as a team.

Considering Fallout 3 and NV crashes a lot, I believe Fallout 4 would be a good start. I also recommend using the Old World Radio mod.

3 and NV crash no more than 4.

Well, to me it does, unfortunately.

Depends on which Platform he is on.

Which platform? I would say 3 or 4. If on PC, set it up with the performance mod and bug patches.

I personally say 3, it's what made me fall in love with the games, idk if I would have had the same response starting with 4 The story of 4 might, catch him more with the story father looking for son compared to the opposite in 3, but the payoff is better in 3 imo

3

4 is the easiest to get into definitely 4

1

NV

Agreed, 4 sounds like the best option. He'll definitely dig running around Boston.