I've got a Wind Waker review! They're both very similar games--sailing a ship around, exploring islands, etc. Though I feel like PH does the sailing and exploring better, and WW does that fighting and on-and gameplay better.

Isn't a Wii backwards compatible for GameCube games

I thought so, but checking online says that only some Wiis are, mostly the ones released earlier. Wikipedia says:

However, redesigned "Family Edition" Wiis and the Wii Mini are not backward-compatible

So check and make sure.

WW is absolutely worth playing, though! It has the best Ganondorf in the series.