I don't have much experience with Metroid. I've played Super Metroid, and I played the NES Metroid on my emulator . . . and that's it. Aside from Super Metroid, I never really played through any of Samus' adventures.
And the first one of you who says, "Samus? You mean like from Super Smash Bros.?!" is getting decked.
Seeing as how I have a GBA emulator, and after having watched gamers suck at various games on Retsupurae, Metroid games included, I downloaded a ROM of Metroid Fusion and Metroid Zero Mission.
I really like Metroid Fusion.
It's faster paced than Super Metroid. Also, you get the Space Ball Jump a lot sooner. Many thanks. Now granted, it takes place on a space station instead of an alien world, so it doesn't have the organic atmosphere that the Metroid franchise is famous for. Also, unlike the other games, a navigator actually tells you where to go. It makes the game substantially easier, but also less "hardcore." Then again, Samus herself remarks that she doesn't like taking orders.
Oh yes, the story in Metroid Fusion is actually pretty interesting. I'm curious to see how things play out.
As for Zero Mission, I don't like that one as much. Samus is much harder to control; her movements are much more spastic. Remember how easy to control Samus was in Super Metroid? Yeah, I miss that. She's even slippier than on Metroid Fusion, which predates Zero Mission. The hell?
On the plus side, if any game deserves a proper remake, it's this one. Yes, you can crouch in Zero Mission, and you can shoot diagnoally too. Also, Zebes actually looks like an alien world now, instead of a featureless series of hallways and vertical shafts. Okay, it's not like the Zebes in Super Metroid, but Nintendo wasn't screwing around either.
Still, I'm playing through Metroid Fusion first. Expect more details later.