not sure the luau at the Polynesian would be a good match for 3 kids age 2 & under...that's a long dinner show, not really aimed at little kids. And it's two table service per person - would be a real bummer if you had to leave early because it was too much for the kids. Maybe 'Ohana at the Poly would be a better fit with the little ones -- activities aimed at kids during the meal there, and doesn't usually take that long to eat there.
Ditto with CRT - not that great of a meal for 2 TS, and with kids that young, would think it would be a waste of TS credits - child under three isn't going to notice a big difference between princesses here or princesses elsewhere, so why not go for the 1 TS meal instead? If you're looking for a princess meal, head over to Epcot/Akershus Princess meals...that's only 1 TS per person and still get lots of princesses - plus there's a bit of a cold buffet so better chance your little ones will have something they like to eat there..
With little ones, I would think they'd enjoy the Winnie the Pooh characters at Crystal Palace buffet in the Magic Kingdom.