I think you mean Metal Gear.

As there wasn't a 2D Metal Gear Solid game.

But yeah... maybe... I don't know.

Final Fantasy was better 2-D. (Though 3-D isn't what screwed it up.)
Mario I liked better 2-D
Zelda I liked Better 2-D

Metroid, Megaman, Castlevania....

Most of my favorite 3-D series are new IPs honestly.

Metal Gear was a 2D game, but (as with my opinion of Zelda) not much changed in terms of gameplay between the Metal Gear games and the early Metal Gear Solid games ...

Grand Theft Auto was also a pretty decent jump, although I thought the games became far less fun when they stopped being 2D.

This is so easy. Mario has. No other game comes close to how Mario64 was recieved and to this day is still leagues ahead of other platformers.

Hmmm.. Mario, Zelda & Metroid went from great 2d games to great 3d games..

But I have to say Flight Simulator..

Worst is Sonic..

Metroid

Hard choice, it's a tough choice between Mario and Metroid.

zelda or Mario i cant choose between the too.

easy question it's Mario without a doubt i understand you can have different opinions but if it isnt mario your opinion is wrong

Mario is the only franchise that kept the same style with a new dimension. They reinvented the platformer to make it play the same with a new dimension. It was still all about jumping. Since the jumps couldn't be as narrow and crazy and hard in 3-D, they added backflips, long jumps, triple jumps, and wall jumps, and adjusted the level design accordingly, and it worked wonders.

In the 2-D Zeldas, the combat was harder than the 3-D Zeldas. They solved the 3rd dimension problem with "locking on" which made it work, but at the cost of difficulty. You can't really run around shooting arrows everywhere in 3-D like you could in 2-D.

Super Mario series and Mario Kart series hands down