90s fo me cause you can get everything with the super nintendo. it was the whole package that Nintendo never achieved again. its top end graphics for a console, and all the third party games, plus great first party support.

Most innovative would be the 80's. Most successful (compared to its competitors, NES was PS2-level dominant) would probably be the 80's. Most profitable? I really don't know. Toss up between the Wii era and the Switch era? Would need someone who knows their profit history to know for sure. Depending on the Gameboy, it might even be the 80's as well.

2020's so far... it is very difficult to re-invent yourself and your most popular IP's 40 years into the business but with the Switch Nintendo has done it all for all!

It's probably the 90s, though it's kind of cheating because the very early part of 1990/1991 is still the NES era and not only just the NES era, but probably the peak of Golden Age "Nintendo Mania", meaning a time where Nintendo was basically bordering on a monopoly of the entire industry and the peak of it was the release of Super Mario Bros. 3 in early 1990 in North America and then later in Europe (it had been released in Japan in '88 though so they were ahead of the curve). The release of Mario 3 was kinda like the apex of the NES cycle and probably the peak point of Nintendo's industry dominance. 

Then you have the SNES era and the N64 era.

Every year in 1990-1999 Nintendo I think legitimately had the GOTY if not the runner up candidate

1990 - Super Mario Bros. 3
1991 - Super Mario World (arguably Sonic wins because it was a newer thing and totally changed Sega's fortunes)
1992 - Street Fighter 2 (SNES exclusive basically), Zelda: Link to the Past and Super Mario Kart would be runner ups
1993 - Star Fox (first big ticket home console release with 3D polygonal graphics), Mortal Kombat probably wins this though
1994 - Donkey Kong Country
1995 - Yoshi's Island or DKC2
1996 - Super Mario 64
1997 - GoldenEye 007 (in a dead heat with Final Fantasy VII)
1998 - Zelda: Ocarina of Time
1999 - Pokemon craze taking over the Western world

That's an unbelievable 10 year run.

The 90s were just more exciting too, there was just crazy stuff happening in a more rapid amount of time. We went from this:

To this:

In only 5 years. 

Thats really is insane list of games, and how are you missing a link to the past one of the best games ever. They were really ahead of their  time in the 90s and it's not even debatable, the games really blew away the competition in the 90s. 

I have it there for 1992, but I have Street Fighter II as the GOTY in '92. SF2 was a monster, monster event in 1992, I remember people paying like $80, even $90 to get it because some retailers were jacking the price of the game through the roof. 

91 (SF2 arcace)

92 (SF SNES)

Was alllll SF2 mania. Like I remember my convenience store by school had to have a line outside the store for people to wait and come in and play SF2 arcade because there too many kids gathering around the machine at one time and it was stopping regular customers from getting inside to get their coffee or bag of chips or whatever, lol. 

I still play street fighter turbo and super turbo on fightcade. Still amazing games, way ahead of their times.

Surprised to see as many votes for the 2020s as for the 1990s, after just three and a half years of the decade, especially considering how strong the 90s were.
Folks must really be loving the Switch era.

It's the battle of nostalgia vs. the present.

Gotta go with the 90s on this one. Nintendo refined all their best games and took some into 3D. The refinement and the leap was major. Aside from the the N64 losing third party games and the gameboy being basically a relic, it was the most epic time as a Nintendo fan for me. Through the entire decade, I could easily justify why Nintendo was No. 1