I think it's kind of tied to the generation it released - as an arcade game most BB games are probably "good", but you're right they're probably not good by today's standards. So many recent games are so much better, so probably not worth the time.
I will say, the later entries got lazier and lazier post arcade era, so I would actually bet the Wiiware and DS entries are pretty bad, personally. The best of the traditional BB games is probably Bubble Symphony or Bubble Memories.
Part 2 is the most different in the series, so I wouldn't consider it a traditional BB game, but I also don't remember it well enough to say if it's good or bad. But of all of them, it's probably the one with the highest chance of still being good.