Personally I always felt that the show didn't really pick up until the season one finale, but there are still some little gems and also there are plot points that are seeded here and there that play a major part. As much as I love the show, I will admit that it's pretty dated. The fx were good for their time but don't always hold up. And the acting and writing definitely can have that soap opera-ish feel. But once the show finds its footing and the stories start to amp up, B5 really starts to shine.
I have all the seasons so I can't really help there. Netflix used to have streaming then dropped it then it had it up again. Other than that you might have to purchase dvds or do the dirty and illegal stream. Wish I could be more helpful