I'm not sure why Zero isn't included.
Resident Evil 2 - An absolute classic, and its use of two scenarios running side by side was great. I've beaten this game so many times that I've lost track.
Resident Evil 1 - Almost as good as 2 to be honest, in fact, some days I want to admit it is better. It has the best scenario in my opinion as it's delivers the most mystery and least action in the series.
Resident Evil 3 - So similar to 2 really, but that doesn't really hurt it as a game, just its initial and overall impact.
Resident Evil 7 - A really good return to form for both the series, and the genre in a way. Yes it is first person, but they put the "Adventure game" back into what clearly had turned into a simple TPS with 4. VR is just icing on the cake.
Resident Evil 5 - I kind of put this on par with 4. To complain about the reduced horror in comparison to its predecessor is silly in my opinion, 4 barely covered that area either. In comparison, its co-op let it down, but its story relevance this time took it up. Overall though, it is that story aspect as well as Wesker's appearance that makes me put it above 4.
Resident Evil 4 - Stand alone, I really like the game, but it still kind of killed the series. To remove the exploration, backtracking and searching for key items took away the best aspects of the genre for me. To add to that injury though was the fact that the beta version of RE4 (with the ghost-hook guy) actually looked really good. Overall, I'm just never going to like a TPS over what we call "traditional" survival horror games.
Resident Evil 6 - Dire, from start to finish.