Smashboards

CJ and Tetromino.

There's the roster.

If you were to ask me, I would also say Mario and Sonic.

Mostly speaking from personal experiences and about my country, but over here Mario and Sonic respectively are bigger than Mickey Mouse and SpongeBob for example altogether. They are the first two who come to anyone's minds when you ask for a videogame character, and they are quite literally everywhere you go.

These past years and months: every toy store, every street, every restaurant, heck even at family reunions with various of my little cousins, there's always at least something Sonic/Mario related there which almost every kid gravitates towards. They are that popular.

So yeah, the second character should be Sonic, at least if you were to ask someone from Spain or the Canary Islands.

Wario Wario Wario I get where you are coming from, but honestly I wouldn't go for CJ.

When someone gets asked about CJ, what likely comes to most people's minds first is "oh yeah, the GTA guy" or the "here we go again" guy. He's iconic for sure, but I'd argue that the GTA games themselves are even more so than the character.
Instead, when someone asks about GTA, they think about the stealing cars mechanic, the cop stars, the radio music and let's be real, the NSFW stuff.

I kinda agree with Tetronimo doh, although if anything I would make Tetris the stage because part of the soul of Tetris is the music and gameplay.

Left Pong paddle and right Pong paddle.