The 1990s featured a split in music styles exaggerating, with wildly popular hits from very different genres. The 90s pop music was almost aggressively cheerful, as evidenced by "Mmm Bop" by teeny boy boppers Hanson.
Yeah, feel free. This was just me taking a stab at it, but obviously there was Jill Sobule, Counting Crows, Verve, Verve Pipe, Merril Bainbridge, Meredith Brooks, Paula Cole, Jewel, TLC, and on and on and on.... Add stuff - go for it!
Lets not forget the importance of the rise of Electronic music to it's underground prominence. Imo the best of this era owes a huge creative debt to the punk subculture, but still manages to remain artistically distinct.