A way to play DS games on a large screen would be nice, but the problem is, how? The remote could take care of touch control, sure thing, but how to pull off the two screens without something terribly awkward? If the two screens are put as in screen shots (
example) on the TV screen, the necessary scaling would likely make the screens pretty small on most TVs, making touch control difficult (I picture the remote being used to point at the screen, and the player pressing A or B to "touch") and possibly defeating the purpose of playing on a bigger screen.
Switching between them, perhaps? Oh, but games in which watching both screens is vital... A challenge. Mario & Luigi: Partners in Time could make it, this way, as could Kirby: Canvas Curse. Phoenix Wright games would be impaired here, with touch control (yeah, you COULD use buttons) and handling other stuff on the touch screen being really important, but all the visuals on the top screen.
There's one last problem... Control. In games like New Super Mario Bros., you used buttons as the main form of control, but there's still the necessity to touch the reserve item every once in a while. With the DS you can hold the stylus between your fingers and maneuver it over to the screen when needed. I can't picture the Wii Remote being used as an efficient cover for the DS's button layout, at all. But it'd be used for touching, no doubt. For those tight situations where you must get that reserve item, how can you do it? Put down the Classic Controller/GameCube controller quickly and grab the remote, point, select, then grab for the other controller? My hands are pretty big, and I can't hold a Wii Remote between my ring finger and pinky easily.
Conclusion: I just don't think there's a way. It'd be great for some games, like Mario Kart DS, Kirby: Canvas Curse, Partners in Time, and to some extent WarioWare: Touched! and possibly Planet Puzzle League. Some games wouldn't get everything out of it, like Brain Age--no microphone. The number of DS games that would play flawlessly without the DS wouldn't be very impressive...