Assuming you said platform rather than console:
Red Dead Redemption on PC
From what I have heard about the game, it would control a heck of a lot better with keyboard and mouse, particularly the galloping and looking around and aiming and shooting all at the same time. Also GTA4 (once tweaked) was so good on PC, Rockstar has shown to create these fantastic naturalistic worlds I just love to look around them with mouse look rather than analogue stick.
Flight Control HD on PC
Again, nice little casual fun game I'd like to play with a mouse rather than touchscreen, I have developed a taste for it on iPad as on display in shops but not like it enough to shell out £420 for the media-tablet. It Just came out on PS3 with Move controls, that I guess is a decent compromise which I'll go for if it is clear there will never be a plain old PC release with mouse support.
Original Tomb Raider series on PSP
The Canucks, Yanks and Mehicans may be surprised by this but the Tomb Raider series has not been entirely released in Europe so no Tomb Raiding on the commute with my PSP. Just got Tomb Raider 1 recently, but I've played that the death, I was hoping for 2, 3 or 5, the games I missed or only played parts of in my childhood.
Metal Gear Solid: Peace Walker on PS3
Yes, I know I just said I have a PSP but while Tomb Raider and other PS1 games is an ideal game for PSP, a game like Peace Walker is not. Far too deep, engrossing and complex to control, I want to play this on a big high resolution screen (and possibly sharpened up polygons) with a proper dual analogue gamepad.
Straight port of Goldeneye 64 to XBLA or Nintendo DS
Yes. Not a bloody remake with Daniel 'Face like a bag of spanners' Craig replacing the great Pierce Brosnan. It's like remaking Thunderball and replacing Sean Connery. In fact they did remake Thunderball 20 years after (Never say Never Again) and they brought back The Sean.
No I love Goldeneye 007 for it's simplicity, it's clunkyness, but most of all its FEEL! That music, those midi sound effects. It's just my N64 is long gone and replacements plus cartridges cost an arm and a leg now.
Killzone HD Re-Release on PS3
HD re-releases are all the rage for Sony today and I can't think of a better example. Killzone was a great game had it not over-extended, it was far too advanced for the PS2 hardware crippled by such limited draw distance and insufferable frame-rate. A HD-re-release would solve all of these problems (so would a PC port but it's a first party game so no dice) and also work as great double promotion for Killzone 3. It could easily run 1080p and 30 fps or 720p and 60fps (probably overkill) but 720p and locked 30fps would be perfect and really give this almost-a-classic a 2nd chance.