F-Zero GX with HD graphics and an online mode would be my #1 choice by miles.

Other than that, Halo 2 and Majora's Mask would be nice. Luckily, both of them should be releasing pretty soon.

Ooh yeah I want Halo 2 as well. Actualy I'm hoping for a Halo Trilogy for the Nextbox as a launch title with all th same kind of enhancements that Halo Anniversary got.

BTW: You might be interested in this link http://www.ign.com/wikis/f-zero-gx/How_to_Unlock_the_F-Zero_AX_Arcade_Game

Apparently there is a way to unlock the F-Zero AX arcade game in F-Zero GX. This whole time an entire second game was under the surface and we didn't know about it. I need to get a Gamecube Gameshark and unlock it myself.

Majora's Mask 3D, Super Mario 64 with the Galaxy Engine or even better with the new 3D HD Engine. Rayman 2 in HD

Metal Gear 1&2 remade into one game. Would be amazing.

Windwaker
Skies of Arcadia
Shenmue

That's about it.

Super Mario RPG: Legend of the Seven Stars

Hmm... That certainly looks interesting. I have an action replay disc so I'll check that stuff out sometime for sure.

It does seem slightly meaningless though since the AX cup and the ten new racers are unlockable even without action replay. Or at least that's the case with my disc. But yeah, I'll check it out for the sake of the new game modes.

Thanks for sharing :)

Jet Force Gemini.
Dino Crisis.

We're already getting the Wind Waker HD so i'm over the moon.

But I would love a Syphon Filter remake. The original was one of faves on the PS1, so to see it in HD with subtle improvements would be awesome.

Turok 2 Seeds of Evil

truly a masterpiece that revolutionized the FPS genre