how come the first 8 season the music was intsrumentel and the final season had words

Cause Roseanne completely lost her mind in the last season. Personally, I think they ruined the intro when they stopped the dinner table opening. That was like a trademark. I hated those morphing things.

2 more ?ins about it why did the song say wre gonna Last Longer and was that Dans Voice?

The reason that there are lyrics in the last episode is because in season 8, I think, Blues Traveller (the band) were guests on the show. They are the ones that sing the lyrics in season 9. I enjoyed the morphing thing. It was kind of a flash back thing. But I also wished they could have incorporated the table sequence into that.