The usual warnings for newcomers.

(1) There was a made for TV movie pilot called "The Gathering" which was made about two years before the show kicks off. It was used to pitch the show. It was released a few years later. Most people consider it an essential episode #0 if you want to watch the show. It's quite bad. The computer graphics were rendered on a bank of Amiga computers...

(2) the first season, up to about the ~15 episode mark, seems quite hokey. There are important story arc details buried in each episode, despite them seemingly being quite disconnected. By about the last third of the first season, it has its legs.

(3) The graphics, sets, and music improve over time. You just sort of have to imagine the first season as a stage play. Unlike Star Trek which had the budget to do models, B5 was comparatively on a shoestring.

(4) There are cast changes between the pilot and episode one; again at the end of season one; and finally, again at the end of season four. Don't be alarmed.