RE4, I'd say yes. My friend played through RE4 on the GCN at least three times, yet when he picked up a Wii and RE4:W, he thought the game got a lot more fun with the Wii controls. As for me, I felt RE4 on the GCN was a little clunky, and never really gave it a chance. On the Wii, I've beaten it at least twice, maybe three times, and I never replay my games more than once.
As for Zelda, I'm not sure. I beat it on GCN, but only played a few minutes of the Wii version. Following the same guidelines as RE4, I'd tenatively say yes, but it's mainly the difference of $30 vs. $50 that makes me have to think. That, and the fact that the Wii controls basically change the way RE4 plays, while Zelda only gets a slight enhancement that may or may not be worth the 30-50+ hour reinvestment.