Mine is 

1.RE 4

2.RE 7

3.RE 2

4.RE 5

5.RE 1

6.RE 3

7.RE 6

RE2
RE4
RE7
RE1
RE3
RE6
RE5

I've only played four of the mainline games but here we go;

1. 5
2. 6
3. 3
4. 1

... Haven't played 1 or 3 since way back on the PS1, and I very much enjoyed both 5 and 6, never understood the hate for either of them, especially 6... I just put 5 first since I've played through it the most times.

I would probably say:

2

3

veronica

1

0

7

6

5

4

Really wasn’t a fan of 4 at all. Really, anything released after Veronica wasn’t very good...

1. RE4
2. RE2R
3. RE7
4. RE3R
5. RE1R
6. RE0
7. RE6
8. RE5

Never beat CV, so I guess I wont count it.

2
4
7 in VR
Veronica
1 Remake
0
5
3
6

From the ones I've played and finished:
4 > 2 > 2R > 5 > 7 > CV > 3R > 3.

I started and never finished 1R and 6.

1. RE4

2. RE remake

3. RE2 remake

4. RE2

5. RE3:N

6. RE7

7. RE3 remake

8. RE5

9. RE:CV

10. RE0

11. RE6

Not sure where to put the original one since I've never played it.

1- RE2
2- RE7
3- RE
4- RE3
5- RE4
6- RE5
7- RE6

Never played Veronica or Zero

I've only played the original trilogy and the two recent remakes. So with that said here is how I'd order them.

1. RE2R
2. RE2
3. RE3R
4. RE3
5. RE1