jet, you are absolutely right - Maui is tops!
We went there twice, once w/out kids, once with them (15 and 11, good travelers), and loved every minute of it!
Do the Road to Hana, visit the 7 boiling pots, go to the top of Haleakala (what a view all the way to the top!), snorkle, and just drive around.
I've been to the Big Island, Oahu - also great, but not as beautiful as Maui.