The launch itself - definitely the Wii. On launch night, my friend and I knew the staff at the local game store where we'd pre-ordered, and they invited us inside. Instead of waiting in a line like so many other launches, we spent the hours until midnight playing games on the store's TVs. Mostly Melee, as I recall.
Runner up - the Nintendo 64. I'd pre-ordered it for $249 at Electronics Boutique, due to arrive on 9/29. Instead, they called a day early, to let me know stores were breaking street date and I could pick it up immediately, Plus, Nintendo had lowered the price, so they owed me back $50. That's hard to beat.
On the game side: the Switch. Breath of the Wild is such a joy, probably my favorite game ever. No other launch game, not even the amazing, world-changing Mario 64, can top it for the best launch experience.
Runner-up: the Gamecube. It's the only console I've picked up pre-launch (US), as I'd imported the Japanese version. Playing Monkey Ball and Wave Race before launch was very cool. And even Rogue Leader, by a couple of days, as instructions to mod the Japanese unit hit the internet a few days before the US launch, which turned out to be quite easy to do, and Funcoland sold me the game 10 days early.
And there you are. All Nintendo launches. Well, what can I say, they're the best. Not that I haven't had great experiences with the other companies, I certainly have. My first Day 1 console, the PS1, was unforgettable. Hell, just that pre-launch demo disc is a thrill. Soul Calibur on Dreamcast was mind-blowing. Even some now quite unimpressive games, like the first few Xbox 360 games I beat - King Kong, Kameo, and Call of Duty 2 - were a memorable thrill to play at that point.
There's hardly been a launch that I didn't love. And I won't shame them here. :)
