The suggested timeline order, as closely as possible, trying to avoid spoilers, given that some episodes/specials are chronologically mixed.
This list is based largely on an amalgam of the responses in the following thread:
https://scifi.stackexchange.com/questions/10009/what-order-should-the-babylon-5-movies-and-series-be-watched-in/21381#21381?newreg=d0bddc65851a4a7fa4c7f0f43045d129
Copied from the following list, but with the specials listed as specials (AKA Season 0) as opposed to movies: