Fair bit of.warning don't get triggerd at my placements this Is my list not yours
1) 4 in my opinion has the best factions out of all the games and combat and gun play are much improved.
2) new vegas the best story, dialog and the voice actors killed it. not as good as 4 in my book but still top 2
3) 76 I know it had a rough start and may still not be up to the others quality but I like being able to play all together with my friends and it has very good weapons and creatures
4) 1 the game that started it all the above view fallout 1 it Is really good but I'm not a fan of the combat system but everything else is good or Great.
5) 3 the game first of the "new type of fallout games" (this opinion is about 8 years old I haven't gotten it to load on my Xbox or pc in that long. It is a gaming pc and can play the others fine and many other much bigger and graphicly better games) when I could play it was good the game play was nice and the characters were too but I didn't like was the lack of faction choice how there is only really 2 factions to choose but the dlcs were nice.
Don't get mad if your favorite isn't my favorite. Try to be nice and give me your list below