You're right Tunutu, as I have said above, it's not just about time but the evolution of the music itself so even the 5th generation has it's particular characteristics, it's not the same as the old rhumba of 20 or 30 years ago.

Zephania, it wouldn't make much sense to class the generations based on the dances as you will find that in one year there are more than 2 or 3 popular dances especially in the 4th generation, the Wenge's were creating several dances on one album.
King Kester Emeneya is known for having made the use of keyboards/synthesizer popular in Congolese music, his singing was the usual but the beats changed,more westernised however you find that it was just him and Koffi who played that style and no one else followed it, they both went back to playing normal rhumba.

For me, Wendo and Grand Kalle were the first age. They started music around the same time. The second age was Franco, Tabu Ley, and Bokelo types. The third generation is where you have the Zaiko clan as well as Soki Vangu, and Pepe Kalle. You have Madilu, Papa Wemba, Evoloko, Koffi Olomide, Ntesa, Josky, Ndombe, Sam Mangwana, Pepe Kalle, Esperent, Dindo Yogo, Djuna Djanana, and some many others. The 4th generation was some of the Quartier Latin musicians like Sam Tshintu, Modogo, and clan wenge like JB Mpiana, Werrason, Blaise Bula, and Adolpe Dominguez. The fifth generation is really Ferre Gola and Fally Ipupa. Fabrice belongs on the six generation coming up soon.

For me, Wendo and Grand Kalle were the first age. They started music around the same time.

I don't think those two should be lumped together. Kalle led the first modern Congolese band, African Jazz, and the style they developed is very different from Wendo's.

Btw, in Terre de la chanson (1996) Manda Tchebwa classifies four generations of Congolese music:
1. 30's-50's: Wendo, Adou Elenga, Feruzi
2. 1950's: African Jazz, OK Jazz, Conga Jazz, Rock-a-Mambo
3. 60's-70's: African Fiesta(s), Vox Africa, Maquisards, Negro Succes, Lovy, Veve, Sosoliso
4. 70's-90's: Zaiko LL, Bella Bella, Empire Bakuba, Shama Shama, Viva La Musica, Victoria Eleison, Langa Langa Stars, Choc Stars, Anti Choc, Big Stars, Quartier Latin etc