Looking at it 12 years later:

Best generation: As far as the overall game experiences, the 7th generation (what Wiki calls the 6th): PS2, Xbox, Gamecube, Dreamcast era. There was such a wide variety of games available in this era because the midsize, "indie" developers still had more of a chance in the market. Nowadays it seems that due to the colossal budgets required for a triple-A game, the same few genres are done to death by a handful of developers. This was also the last generation where online wasn't an integral part of most games. It was the pinnacle of the "buy a game at the store and fire it up" mentality; all you needed was the console, a controller, the game, and maybe a memory card.

Worst generation: The last one, the 9th (Wiki 8th). What did we add with this generation? By this time, you'd often buy a game, you'd need a 10, 20, even 50 gigabyte download. Your console also has to be connected to the internet. So, you buy a game, you get it home, you have to wait half an hour or more to play it. And it's probably some game that's the same genre as 467 others that came out that same year. After constant progress from the 1970s through the 2000s, the 2010s has seen a backslide. No, I don't want a 37 gigabyte patch. No, I don't want to have to play online. The one good thing is that consoles have hard drives now, but that was in the previous generation as well. This generation added nothing meaningful, unlike every generation before it.

I know the 6th generation (Wiki 5th) gets a lot of flack, but it introduced a lot of features that improved the gaming experience. 3D, for one. I know the early 3D often looked ugly, but it progressed quickly; most of the later 6th gen (1998 and later) games looked significantly better than the early (1995 to 1997) ones. (And I'm talking about the true 6th gen consoles, PS1, N64, and Saturn) There are certain game genres that hugely benefited from 3D. I know many will disagree with me but 3D is almost a requirement for RPGs, and I enjoy the 3D platformers more than 2D ones. Also, analog sticks, CD storage (which facilitated longer and more complex games), much more widespread game save features, and a myriad of other things. It was a quantum leap in just a few years.